noun

• (US) A double-ended vessel, generally of stainless steel or other metal, one end of which typically measures 1½ fluid ounces (approx. 44 ml), the other typically 1 fluid ounce (approx. 30 ml).
  "A good jigger will have a well formed lip that will pour a clean stream into the cocktail shaker or glass."
• (US) A measure of 1½ fluid ounces (approx. 44 ml) of liquor.
  "“People are so dam’ sensitive about colour around here that you can’t even ask a barman for a jigger of rum. You have to ask for a jegro.”"
• (US, slang) A drink of whiskey.
• (mining) The sieve used in sorting or separating ore.

verb

• (transitive) To alter or adjust, particularly in ways not originally intended.
  "You'll have to jigger it from the original specifications to get it to work."
• (pottery, transitive) To use a jigger.
• (transitive) To move, send, or drive with a jerk; to jerk; also, to drive or send over with a jerk, as a golf ball.
  "He could jigger the ball o'er a steeple tall as most men would jigger a cop."

noun

• (slang, archaic) A prison; a jail cell.
  "According to a disciplinary notice, a correctional officer saw a "jigger string" coming from cell H-2 to Harper's cell. A jigger string is used to move objects between cells."
• (dialect, Liverpool, dated) An alleyway separating the backs of two rows of houses.
  ""It's jus' through this jigger and round the back of the next block." She hurried through the alleyway in front of me; the pressing back-yard walls prevented anything more than single file."
• (slang, euphemistic, dated) The penis.
  "Well, they saw a little boy on the street and his penis was hanging out and they said his "jigger" was hanging out, and I said, "Well, maybe his mother didn't tell him differently.""
• (slang, euphemistic) A vagina.
  "A tiny pulse from Lisette's thigh beat under my ear: stroke, stroke, stroke. I contemplated the thick red bush of her jigger, so close to my face."

verb

• (slang, obsolete) To imprison.
  "...offering to swear an alibi for the prisoner [...] to ensure an acquittal. Terms: £50 for value received. No pay if jiggered."
• (slang, archaic) To confound; to damn.
  "jigger me, but I think you be turning jest into earnest,"