During gay sex the 'Bottom' is the partner who received the penetration from the 'top'.
Bottom's may have other designations such as: Passive, Cole, Submissive.
In gay culture it is possible to tell which partner is a bottom by their characteristic mannerisms.
I met a Cole the other day, he was such a bottom.
Person 1: haha you’re such a bottom
Yiurz: no im not >:(
Person 1: thats not what you said last night babe
look at that bottom bitch, Seren. they are such a bottom, that when you look up "bottom" on urban dictionary, this definition pops up
Bottom also refers to ones named Julian.
"Man I wish I have a big booty bottom right now.
Dude why don't you just call Julian."
"do you wanna watch bottoms?"
"no, It's so hard to pirate!"