blerrrrgggghhh!!!!..... if you didn't know this, you obviously need to go back to 3rd grade!

no! it is not ante/post- MERIDIAN (a.m./p.m.). it's "MERIDIEM!!!!!" 

meridian pertains to a map/globe's longitude in connection to the international date line.

meridiem is the latin term for noon or mid-day.

also, anti-meridian has nothing to do with a.m. it is the longitude 180 degrees east or west of the international dateline.

thank you. that is all.

what can i do? ^__^