"coniferous tree," Old English pin (in compounds), from Old French pin and directly from Latin pinus "pine, pine-tree, fir-tree," perhaps in reference to the sap or pitch, from PIE *peie- "to be fat, swell" (see fat (adj.)). Cf. Sanskrit pituh "juice, sap, resin," pitudaruh "pine tree," Greek pitys "pine tree." Also cf. pitch (n.1). Pine-top "cheap illicit whiskey," first recorded 1858, Southern U.S. slang. Pine-needle (n.) attested from 1866.