Meaning

• An effigy of a man burned on a bonfire on the anniversary of the Gunpowder Plot (5th November).

• A person of eccentric appearance or dress; a "fright".

• A man, fellow.

• (especially in the plural) A person (see usage notes).

• (of animals and sometimes objects) Thing, creature.

  "The dog's left foreleg was broken, poor little guy."

• Thing, unit.

  "This guy is the partial derivative of that guy with respect to x."

• (term of address) Buster, Mack, fella, bud, man.

  "Hey, guy, give a man a break, would ya?"

Meaning

• To exhibit an effigy of Guy Fawkes around the 5th November.

• To make fun of, to ridicule with wit or innuendo.

• To play in a comedic manner.