One of the lowest designations for a girl in the Hotness index. A tankable is a girl that you need at least a 6 pack in you before you think about having sex with
1. of a high level of beauty; desribing someone you would like to tuck in to. Adj.
2. of a high enough level of promiscuity as to be considered easy to tuck in to. Adj.
1.
"Dude, I fully wanna tuck in to Sophie tonight, she's bang tidy."
"Yeah man, she's tuckable"
2.
"Anyone could have a go on Katie if they wanted, she's easily tuckable"