WordNet sense 1 (any grammatical case other than the nominative):

oblique case

WordNet sense 2 (a diagonally arranged abdominal muscle on either side of the torso):

external oblique muscle, abdominal external oblique muscle, musculus obliquus externus abdominis

WordNet sense 3 (indirect in departing from the accepted or proper way; misleading):

devious

WordNet sense 4 (extended senses; not direct in manner or language or behavior or action):

indirect