look up any word, like fellated:
 
1.
An important day, very much like an anniversary, but it is celebrated in terms of months, as opposed to anniversaries which are celebrated in terms of years. The only difference is that there are only 11 monthsaries for a certain event, the 12th would already be an anniversary.
If a couple got together on April 18, their monthsary, rather, monthsaries, would be on May 18, June 18, July 18, ..., until March 18 of the following year. Then, The next 18th, which is April, would be logically, their first anniversary.
by Jazz Casumbal May 17, 2006
 
2.
refer to number 2 above.

dis-etymology:

a corruption of anniversary, "anniversarius" latin for "annus" (year) + "versarius" (to go back to or revisit).

disambiguation:

1. "month" in latin is mensis. thus, it should be "mensiversary", or menses for brevity, since anybody who celebrates this thing, more likely than not, is having his/her monthly period.

2. since "month" is named after the moon (luna in spanish), then it is very safe indeed to consider that anyone who celebrates this event is a lunatic.
1. There is no such word as monthsary.
2. Girl: Honey, it's that time of the month again!

Guy: (To himself) Oh crap, just great! I just bought a couple of viagras and now this. I'm going out for a beer.

Girl: What are you talking about? It's our monthsary!

Guy: (has already ran out the door) ...
by ahmedy February 27, 2009
 
3.
same as anniversary but celebrated monthly rather than a yearly basis.
rodjun and i are having our 3rd monthsary tomorrow.
by mykz January 02, 2008
 
4.
Commonly used among Filipinos. Its actually supposed to be monthiversary. for some reason they use it. monthsary mean that a couple has been together for a month, thus, monthsary! used rather than anniversary coz couples are playas and bitches enough to be together for only a meager amount of time.
DICK 1: Hayy! Its our monthsary! lets go to teh mall!
DICK 2: ITS MONTHIVERSARY sucka
by joshuatree January 02, 2008
 
5.
a celebration of an anniversary, only by month
It's Ahmed Paglinawan's 11th monthsary in Facebook.
by mookee February 26, 2009