H M

Horizontally making out.

“We H M’ed last night on the couch.”

(u)Mm h(u)m

Affirmative grunt, agreeance; acceptance, something yummy or tasty.
A moan of delight.

Friend: "Hey, do you like that apple pie?"
You: " (u)Mm h(u)m!"

H A M

H A M

PERSON 1: H A M
PERSON 2: H A M