(idiomatic) A quiet, non-participating, or unseen observer; an eavesdropper or witness.

A poster, especially for advertisement purposes, put up illegally / One who posts such posters

present participle of fly-pitch

The act of posting posters in prohibited or illegal areas, especially for advertisement purposes

present participle of fly-post

A poisonous and hallucinogenic mushroom, Amanita muscaria, with a large crimson cap, fading to yellow, scattered with white flecks.

(dated) a military aviator who had shot down many enemy aircraft

(idiomatic) To depart hastily or unannounced; to escape or flee. / (of a bird) To escape from a pen or similar enclosure.

(slang) An aircraft with an unacceptably high accident rate.

(idiomatic) To act in a manner highly contrary to; to counteract or contradict.