Green’s Dictionary of Slang

polish... v.

used in combs. to mean to masturbate, or to fellate e.g. polish Charlie Brown, ...one’s antlers, ...one’s bayonet, ...one’s knob, ...one’s sword, ...percy, ...the lighthouse, ...the penguin, ...the pole, ...the rocket, ...the sword, ...the viper.

D. Crane Wife’s Young Lover at neatopotato.net/xnovel 🌐 You polished my shoes… now I’m going to polish your sweet young peckerhead.
[Aus]Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Polish. To fellate.
[US](con. c.1970) G. Hasford Phantom Blooper 13: Inside the only guard bunker still standing in our area, our New Guy is busy choking his lizard [...] polishing his bayonet, just a little early-morning organ practice to cut the edge off the cold.
[US]C. Hiaasen Native Tongue 161: Minnie on her knees, polishing Mickey’s knob – whoever did the drawing was damn good.
M. Whittemore ‘Little Billy Burlap and His Dog Butt-cheese’ Part Seven at NaughtyStory.com 🌐 Billy was getting extremely close to blowing his cookies, sitting there naked, polishing his rod, watching two girls getting off on each other.
Bill Healey ‘U4ME’ [poem] on Originality 🌐 Giving the tadpoles a swimming lesson, coming into your own / One-eyed target practice, polishing the bone / Doing a George Michael, stroking your poker / Makin a living as a chicken choker.
[Aus]R.G. Barrett Mystery Bay Blues 152: He said nothing about the porking and the polishing.

In phrases

polish someone’s gun (v.)

see under gun n.1