Phrase guide

critical angle

noun · 4 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 angle of incidence beyond which light traveling through a medium experiences total internal reflection upon encountering a boundary with a less refractive medium.

Definition source: English Wiktionary via Wiktextract

Topics: engineering, natural-sciences, optics, physical-sciences, physics

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

The angle of attack beyond which an airfoil stalls, experiencing a decrease in lift and increase in drag due to separation of airflow from the upper surface of the airfoil.

Definition source: English Wiktionary via Wiktextract

Topics: aeronautics, aerospace, aviation, business, engineering, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

The angle beyond which a ramp or a set of stairs is considered uncomfortable or unsafe.

Definition source: English Wiktionary via Wiktextract

Topics: architecture

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

noun

Meaning 4

the smallest angle of incidence for which light is totally reflected

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: angle of incidence, incidence angle

History

Etymology

No etymology was provided for this word.

Across languages

Translations

4 source translations are retained for this English entry.

  • Arabic: زَاوِيَة حَرِجَة — smallest angle of incidence
  • Bulgarian: граничен ъгъл (graničen ǎgǎl) — smallest angle of incidence
  • Polish: kąt graniczny — smallest angle of incidence
  • Tagalog: maselang siha — smallest angle of incidence