Basically, if your a snack person, snunch is snack + lunch, the first snunch was on the day this was posted to urban dictionary, October 2021 on Day 16
GUY 1: why did you get alot of snacks at that convenient store
GUY 2: don't you remember, we're doing snunch
A combination of a snack and lunch; it's a little too late for lunch, yet close to snack time.
"Hey Mom! Can we stop at McDonald's for snunch? Dad forgot to fix us lunch."