Green’s Dictionary of Slang

ow n.

[? abbr. + O n. (2); although it predates this]

(US drugs) the bowl of an opium pipe.

Show quotations
[US]L.J. Beck N.Y.’s Chinatown 147: This layout consists of [...] The Yen Tsiang (opium pipe), Ow (opium bowl), Yen hock (a thin wire used for dipping out the opium and holding it over the light while cooking).