noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   A nonessential amino acid formed by the oxidation of cysteine; it contains two cysteine residues linked by a disulfide bond. countable, uncountable
2. 2
   a crystalline amino acid found in proteins (especially keratin); discovered in bladder stones wordnet

Synonyms

All synonyms

e921e921 when used as an improving agent

Etymology

From Ancient Greek κύστις (kústis, “bladder”), where it was found.

Related phrases

cystine knotnonessential amino acid

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.