wig v.1
1. [1930s+] (US) to talk, to chatter.
2. [1950s] (US black) to inform, to explain to someone.
3. [1930s+] to annoy, to irritate, to render someone nervous.
4. [1950s] (US black) to delight, to impress.
5. [1950s] to understand, to approve.
6. [1950s+] (US) to play cerebral, intellectual jazz music.
7. [1950s+] (US) to be in good spirits, to enjoy.
8. [1950s+] (US) to become nervous, hysterical, overly stressed, mentally unbalanced.
9. [1960s+] (US) to reach a different state through drugs.
In phrases
1. [1950s+] (US, also whig out) to lose control, to have a breakdown; thus wigged (out) adj.
2. [1950s+] (orig. jazz) to enjoy oneself, to lose one’s inhibitions, to be thrilled by.
3. [1960s+] (US campus) to shock, thrill or amaze someone, whether positively or negatively.