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.
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noun
An essential amino acid, C6H13NO2, isomeric with isoleucine, found in most animal proteins; it is essential for growth in children.
Definition source: English Wiktionary via Wiktextract
Usage: countable, uncountable
Topics: biochemistry, biology, chemistry, microbiology, natural-sciences, physical-sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
a white crystalline amino acid occurring in proteins that is essential for nutrition; obtained by the hydrolysis of most dietary proteins
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
Broader terms: essential amino acid
History
Etymology tree Proto-Indo-European *lewk- Proto-Indo-European *-ós Proto-Indo-European *lewkós Proto-Hellenic *leukós Ancient Greek λευκός (leukós) Proto-Indo-European *-nós Proto-Indo-European *-iHnos Proto-Italic *-īnos Latin -īnusder. Old French -inbor. Middle English -in English -ine English leucine Derived from Ancient Greek λευκός (leukós, “white”) + -ine, equivalent to leuco- + -ine.
Across languages
21 source translations are retained for this English entry.
