To be exceedingly happy and content.
The full phrase is "happy as a clam at high tide." Clams can only be dug up at low tides, so at high tide a clam is safer and secure, so therefore, happy.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).
Precedes or follows either a gratuitously disrespectful or honest remark, originated in New York City. Used in similar fashion to "no offense" or "to be honest," interchangeably.
Ya mans is wild buns, respectfully. Respectfully he's washed.
After school, The Modells on Jamaica Ave was active. Respectfully.