When spelled coupé
it is pronounced
and means cut
and something like leap
In Ballet the leap is done with one foot cutting away the other, to replace it. The foot can cut under as in a coupè dessous or the foot can cut over as in coupè dessus.
In this context, the leap sometimes travels through the air like a real leap, as in coupè dessous sautè, or it might never leave the ground, as in a coupè dessous par terre.