Phrase guide

theta wave

noun · 2 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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1

noun

Meaning 1

A type of electrical activity in the brain; a brain wave with a frequency of 4-8 hertz.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

the normal brainwave in the encephalogram of a person who is awake but relaxed and drowsy; occurs with low frequency and low amplitude

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: theta rhythm

Antonyms: none provided

Broader terms: brainwave, brain wave, cortical potential

History

Etymology

From theta + wave.

Across languages

Translations

1 source translations are retained for this English entry.

  • Spanish: onda theta — electrical activity in the brain