1. The politically correct term for a "bachelor party" (or "bachelorette party"). Typically used to avoid the negative connotations associated with bachelor parties. 2. A celebration prior to a couple's wedding.

Benefit of the word: If used quickly, the listener may think you said "reunion" celebration and will not question you regarding a "pre-union" celebration.
Wife Scenario 1:

Husband: "Honey, can I go to Vegas for Bob's bachelor party next weekend?"
Wife: "No."

Wife Scenario 2:

Husband: "Honey, can I go to Vegas for Bob's pre-union celebration next weekend?"
Wife: "Sure honey, have fun."

Hotel Scenario 1:

Hotel: "Hello, this is Fancy Hotel."
Caller: "Hi, I would like to book a suite for a bachelor party!"
Hotel: "I'm sorry sir, we do not allow bachelor parties at Fancy Hotel due to excessive damage, drug use and prostitution that is typically associated with them. Good-bye."

Hotel Scenario 2:

Hotel: "Hello, this is Fancy Hotel."
Caller: "Hi, I would like to book a suite for a pre-union celebration!"
Hotel: "Excellent, sir. How many guests will be staying with us?"
by theSchneid June 14, 2011
Get the pre-union celebration mug.