cystathionine

noun
cys·​ta·​thi·​o·​nine | \ ˌsis-tə-ˈthī-ə-ˌnēn How to pronounce cystathionine (audio) \

Medical Definition of cystathionine

: a sulfur-containing amino acid C7H14N2O4S formed as an intermediate in the conversion of methionine to cysteine