Definition of "harman"

I Frisky Moll, with my rum coll, / Wou'd Grub in a bowzing ken; / But ere for the scran he had tipt the cole, / The Harman he came in.

1724, “Frisky Moll's Song”, in Farmer, John Stephen, editor, Musa Pedestris, published 1896, page 41

I pray you now send me some dub, / A bottle or two to the needy. / I beg you won't bring it yourself, / The harman is at the Old-Bailey; / I'd rather you'd send it behalf, / For, if they twig you they'll nail you.

1765, “A Song in High Life”, in The Merry Medley, volume 1, London: W. Hoggard, page 35

Harman is a common compound in several foods, plants and beverages. Numerous studies have demonstrated its mutagenic, co-mutagenic and carcinogenic effects; however, the exact mechanism has not been fully identified.

2010, El Gendy MA, El-Kadi AO, Harman induces CYP1A1 enzyme through an aryl hydrocarbon receptor mechanism., Toxicology and Applied Pharmacology, page 55