Green’s Dictionary of Slang

batshit v.

[batshit n. (1)]
(US)

1. to tell lies, to tease, to confuse with false information.

[US]Current Sl. V 19: bat-shit, [...] v. to chat.

2. to gossip, to chatter inconsequentially.

[US]Current Sl. V 19: bat-shit, [...] v. to [...] b.s.