An exclamation to point out a sexual innuendo, or to create it regardless its existence. May be used in the same way of "That's what she said" but without the limitations of the later. Given it is the catch phrase of Family Guy's kinky character Quagmire, the use of "gigidy" denotes a deviant sexual innuendo.
1. Used to express sexual attration or intent if used in the most explicit form.
2. More likly used as an exclimation of sorts ranging from displeasure to approval.
Originated from the Quagmire character on the TV show Family Guy. He uses the word in the first manner. As a note this word is hardly used along, instead it tends to repeat itself several (commonly two or three) times in a row.