In the TNG episode The Naked Now, the crew of the Enterprise come across a strange contagion which they discover is almost identical to one found by the Enterprise under Captain Kirk:
RIKER: Historical. That's it. I remember I was reading a history of all the past starships named Enterprise.
DATA: Enterprise history. Aberrant behavior. Medical cross reference.
RIKER: Captain, I believe we've have the answer to what happened over there.
PICARD: The Constitution class Enterprise, Captain James T. Kirk commanding.
RIKER: Similar conditions. They were monitoring a planet that was breaking up, not a collapsing star as in this case. But there were the same huge shifts in gravity ...
PICARD: Which somehow resulted in complex strings of water molecules which acquired carbon from the body and acted on the brain like alcohol.
Out of universe, this is obviously a nod to TOS, but is it a nod to a specific episode/event from TOS, or just to the Kirk era as a whole?