abbreviation for "make-out session". quality time spent in the batter's box and at first base.
-longer than just a quick kiss - at least five minutes of dedicated snogging.
-always involves horizontality

Short for make out session. Refers to a long period of making out. To be considered a session, it should probably be at least 15 minutes long. A session is usually not random or spontaneous but can be in some cases.