to dry hump someone of the same sex once with great vigor while they are bending over while shouting "OOST!", perhaps while they are picking up somthing. idealy an oost should knock someone over. oosts can be performed from a standstill or with a run up.
mr a is bending down to tie his shoelace and mr b runs up behind him, performing a running oost that knocks him flat on his face.
by heinzie July 10, 2008
by jessebakesyourdad August 07, 2015