Phrase guide

lizard brain

noun · 3 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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No pronunciation record was provided for this word.

1

noun

Meaning 1

The most primitive part of the brain; the brain stem.

Definition source: English Wiktionary via Wiktextract

Usage: informal

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

Any part of a person's psyche or personality dominated by instinct or impulse rather than rational thought.

Definition source: English Wiktionary via Wiktextract

Usage: broadly

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: id, reptilian brain

Antonyms: none provided

3

noun

Meaning 3

Any part of a person's mind concerned with automatic, repetitive tasks rather than emotion.

Definition source: English Wiktionary via Wiktextract

Usage: broadly

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

No etymology was provided for this word.