backsides
/bakˈsʌɪd/
/ˈbaksʌɪd/
noun
A person’s buttocks.
buttocks,behind,backside,bottom,rear,rear end,seat,haunches,cheeks
adjective
(of a manoeuvre in surfing and other board sports) done clockwise for a regular rider and anticlockwise for a goofy rider.
Next would be big backside floaters or under the lip lay back snaps.