Standard Lemma guide
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
Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.
noun
The simultaneous turning of both eyes when focusing.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Topics: medicine, physiology, sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
A measure of convergence or divergence of rays.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Topics: engineering, natural-sciences, optics, physical-sciences, physics
Synonyms: none provided
Antonyms: none provided
noun
The direction of the overturned component of an asymmetric fold.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Topics: geography, geology, natural-sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
From verge (“tend, incline”, from Latin vergere) + -ence, synonym of earlier (1660s) vergency (the equivalent of French vergence). Coined as a technical term in ophthalmology, as a hypernym of convergence and divergence, in 1902. The sense of the numeric quantity in geometric optics was introduced, from use of the term in physiological optics, in the 1920s.
