datemare 

a date so bad you shudder with bad flash backs.

my date with Al was so bad I had datemares for days.

datemare by CC Burke January 20, 2009

datemate

A gender neutral term to describe your partner before you're engaged or married. Used in place of "boyfriend" or "girlfriend".

"My datemate first asked me out last june, we've been together for almost a year now!"

datemate by whattheheckie February 2, 2014

Datemarks 

Significant dates on the calendar around which you schedule important activities, such as vacations, ATS and cool surprises for your secretary.

Datemarks for January 2006:
- Mon, Jan 2nd is New Year's Day (observed)
- Mon, Jan 9th is the First Day of Instruction for UH
- Mon, Jan 16th is Martin Luther King, Jr. (holi-)Day

Datemarks by ck, Hawaii Undersea Research Lab December 16, 2005