2gin 堅 — real, true, genuine, not fake, powerful (the opposite of làuh 流, dyj 68, 30).
3gin dihng làuh gaa? 堅定流架? — a way of inquiry into the status of someone or something, "Is this stuff real or is it fake?", "Is he for real?".
4gin làuh 堅流 — drugs (drug-addict jargon).
5gin làuh jōng 堅流裝 — one tenth of a cap of drugs (drug-addict jargon), cf. hok 核.
6gin líu 堅料 — genuine stuff, high quality or real goods (e.g. drugs, "the genuine article" (dyj 43, 28); a good or trustworthy person, a person with the required qualities (hdk 49, 26).