noun Date: 1949 the levorotatory form of tryptophan that is a precursor of serotonin and was used formerly as a dietary supplement especially to promote sleep and relieve depression
L-TRYPTOPHAN
Meaning of L-TRYPTOPHAN in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012