Depression can impact how you feel, think, and act. Like many medical conditions, depression has a language all its own, with technical terms and descriptions. The glossary below will help you better understand the words associated with depression.

Adjustment Disorder

A group of symptoms, such as sadness and hopelessness, that happen after someone experiences a stressful life event.


The inability to feel pleasure.


Medications that are used to treat depression. There are different types of anti-depressants including: selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic anti-depressants, monoamine oxidase inhibitors (MAOIs), and atypical anti-depressants.

Antidepressant Withdrawal Syndrome

A condition that happens when someone stops taking anti-depressants. It can cause symptoms such as trouble sleeping, nausea, poor balance, flu-like symptoms, or anxiety.


Medicines used to treat psychosis.

Atypical Depression

A subtype of depression marked by excessive sleepiness, increased appetite, and a mood that can improve in response to positive events. Despite what its name might suggest, atypical depression isn’t rare or unusual; it just differs from “typical” depression, notes the Cleveland Clinic.


A lack of initiative or motivation to accomplish tasks.

Anxiety Disorder

A mental health condition that causes intense and excessive worry or fear about everyday situations. People with anxiety disorders often have panic attacks.

Behaviour Activation Therapy

A type of therapy that encourages people to do more activities that bring them enjoyment or a sense of accomplishment, according to Michigan Medicine.

Bipolar Disorder

A disorder that causes episodes of extreme mood swings that vary from depressive lows to manic highs. This was formerly known as manic depression.

Black Box Warning

The strictest warning the U.S. Food and Drug Administration (FDA) places on a prescription drug label when a medicine is thought to pose a serious risk.

Borderline Personality Disorder

A mental health condition that’s characterised by a difficulty with regulating emotions. Borderline personality disorder can lead to unstable behaviour, moods, and relationships.


Being immobile or unable to move.

Chronic Depression

A type of depression that causes symptoms that last at least two years.

Clinical Trial

A study that offers participants a new treatment or procedure in order to determine its effectiveness.

Cognitive Behavioural Therapy (CBT)

A type of talk therapy that encourages patients to identify unhelpful thinking patterns and change their behaviour.

Deep Brain Stimulation

A procedure that involves implanting electrodes in the brain to produce electrical impulses that stimulate specific areas. It may be used to treat some forms of depression that have not responded to other treatments.


A false belief that a person holds even though there is strong evidence against it.


A disorder that causes someone to feel disconnected or detached from their own body and thoughts.


A mental health condition that causes symptoms such as sadness, feelings of worthlessness, excessive guilt, or a lack of interest in daily activities. It can affect a person’s work, sleep, appetite, and social life, according to the National Institute of Mental Health (NIMH).

Diagnostic and Statistical Manual of Mental Disorders (DSM-5)

A handbook used by doctors, psychiatrists, and other mental health professionals to diagnose mental health disorders. The latest version is called the DSM-5.

Differential Diagnosis

An explanation of how a person’s diagnosis is different from other conditions that cause similar symptoms.

Disruptive Mood Dysregulation Disorder

A childhood or adolescent condition that’s characterised by extreme anger, irritability, and temper outbursts.


A brain chemical that helps regulate how a person feels pleasure.

Double Depression

A condition that occurs when major depression episodes develop on top of pre-existing dysthymia.

Dual Diagnosis

Having a mental health condition and also a drug or alcohol issue at the same time.


A type of chronic, low-grade depression that’s less severe than major depression but still prevents normal functioning. Dysthymia is also sometimes called persistent depressive disorder.

Electroconvulsive Therapy (ECT)

A treatment for depression that involves delivering an electric current to the brain through the scalp to induce a controlled seizure. It’s generally used only when a person doesn’t respond to psychotherapy, medications, or other therapies.

Emotional Freedom Technique (EFT)

An alternative treatment plan that may involve methods such as tapping or psychological acupressure.


Chemicals in your body that help you cope with stress or pain.

Euthymic State

A normal, tranquil mental state or mood.

Flat Affect

A condition in which people express very little of their emotions. For example, someone with a flat affect may not show facial expressions.


Seeing, hearing, touching, smelling, or tasting something that’s not really there.


Excessive daytime sleeping or sleepiness.

Light Therapy

A treatment, which is also known as phototherapy, that involves exposing someone to artificial light. It’s thought to ease symptoms of seasonal affective disorder (SAD) by targeting brain chemicals linked to mood and sleep.

Major Depressive Disorder

A depressive disorder that lasts two weeks or more and significantly interferes with someone’s daily life, according to the NIMH. Symptoms might include feelings of hopelessness, fatigue, and low energy.


An unusually elevated or irritable mood.


Taking very small amounts of a certain drug.

Mood Stabilizer

Medication used to treat some types of depression, such as bipolar disorder. They include anti-convulsants and lithium.

Narrative Therapy

A type of counselling that helps identify and shift the stories or narratives people tell about their lives.

Negative Affect

A negative outward manifestation of emotion.


A type of therapy used for depression that teaches a person to alter their brain activity through intensive brain training exercises.


A type of psychologist who specialises in understanding the connection between the brain and certain behaviour.


The body’s chemical messengers. They’re used by the nervous system to transmit messages between neurons, or from neurons to muscles.


A chemical in the body that affects a person’s mood and how their brain responds to stressful events.

Panic Attack

An episode where a person feels intense fear or anxiety accompanied by physical symptoms. Panic attacks are common in certain anxiety disorders.


A persistent, extreme, irrational fear of an object, person, animal, activity or situation, notes Harvard Health Publishing. Common examples include arachnophobia (a fear of spiders), acrophobia (a fear of heights), and agoraphobia (a fear of being in public places where it would be difficult or embarrassing to leave if panic arises).

Peripartum (Postpartum) Depression

A type of depression that affects women who have recently had a baby and lasts two weeks or longer. It is not the same as “baby blues,” which is mild, shorter than two weeks, and more common, according to Mayo Clinic.


An intervention with the family or friends of someone who commits suicide.

Premenstrual Dysphoric Disorder (PMDD)

A condition that causes irritability, depression, or anxiety about a week or two before a woman starts her period. Symptoms typically go away two or three days after menstruation begins.


A medical doctor who specialises in treating mental or behavioural disorders. A psychiatrist can prescribe medicines.


A professional who has an advanced degree and specialises in helping people with mental health disorders with techniques such as psychotherapy. Psychologists aren’t medical doctors and can’t prescribe medicines to patients.


A term used to describe a condition in which someone loses contact with reality. They may experience delusions, hallucinations, paranoia, or difficulty thinking logically.


A type of therapy that involves talking to a mental health professional. It’s sometimes used along with medications.

Psychotic Depression

A type of depression that’s accompanied by delusions, hallucinations, or another form of psychosis.

Post-Traumatic Stress Disorder (PTSD)

A mental health condition, PTSD is triggered by experiencing or witnessing a terrifying event.

Rating Scale for Depression

A measuring scale that helps to identify the severity of a person’s depression.

Repetitive Transcranial Magnetic Stimulation (rTMS)

A type of treatment that uses a magnet to target and stimulate certain areas of the brain through the skull. It’s used to help depression and anxiety.

Schizoaffective Disorder

A chronic mental health disorder that’s characterised by symptoms of schizophrenia (such as hallucinations) and a mood disorder (such as bipolar disorder).

Seasonal Affective Disorder (SAD)

A type of depression that happens at about the same time each year. SAD usually occurs in the fall or Winter and ends in the Spring or Summer, according to NIMH.


A chemical in the brain that affects a wide range of functions, including mood and feelings of happiness.

Situational Depression

A type of depression that develops after a traumatic or stressful event. It’s also known as reactive depression and usually goes away after a short amount of time.

Social Anxiety Disorder

A type of mental health condition that causes anxiety in social situations.


Additions that are used in the DSM-5 to further describe a condition and give more specifics about a diagnosis.

Substance/Medication-Induced Depressive Disorder

A condition characterised by depressive symptoms that occur during or soon after a person takes a certain medication or substance or experiences withdrawal from a certain medication or substance.


A term used to describe when someone exhibits symptoms that aren’t severe enough to warrant a diagnosis of a particular disorder.

Suicidal Ideation

Thinking about suicide or planning suicide.

Thought Insertion

When a person with psychotic depression believes their thoughts are not their own and have been ‘inserted’ into their mind.

Treatment-Resistant Depression (TRD)

A type of depression that doesn’t respond to typical treatments.


A situation or event that provokes symptoms of depression.

Vagus Nerve Stimulation

A procedure for treatment-resistant depression that involves using a device to stimulate the vagus nerve in the body. The vagus nerve connects the brain to the body and is thought to be involved in regulating mood.