Green’s Dictionary of Slang

tee-hee n.

In phrases

big tee-hee (n.)

(US) something that provokes laughter.

[US]Wash. Times (DC) 16 May 16/4: We were prepared for a big tee-hee. Instead of a laugh [...] we received a distinct shock.
Dly Jrnl (Franklin, IN) 16 Nov. 2/3: A Carter presidency clearly is not going to be a riot of giggles [...] Not, mind you, that it should be one big tee-hee.
give someone the big tee-hee (v.)

(US) to laugh at.

[US]D. Runyon ‘The Defence of Strikerville’ in From First To Last (1954) 12: We didn’t want the gang [...] to give us the big tee-hee.
[US]Eve. Star (Wash., DC) pt 3 16 Nov. 3/2-3: A young ‘fluff,’ applying for ‘bale’ [...] was given the big tee-hee ’cause she couldn’t prove her age.