Comes from the term "gig". It means you are moving from one gig to the next, singing along with each band for a few songs and then moving on. It's similar to clubbing, except the clubs are more likely to be coffee shops and there will probably be more singing and less dancing/drinking. Gigging is about experiencing the music and atmosphere of each venue. Tends to be more popular with people who enjoy jazz or "underground" music.

To catch bull frogs to use as fishing bait/ food. Above said frogs are caught by means of spearing with a frog gigg (either a forked or pointed apparatus)

the act of becoming overly excited