Antonyms of adj decumbent

1 sense of decumbent

Sense 1
accumbent, decumbent, recumbent -- (lying down; in a position of comfort or rest)

INDIRECT (VIA unerect) -> erect, vertical, upright -- (upright in position or posture; "an erect stature"; "erect flower stalks"; "for a dog, an erect tail indicates aggression"; "a column still vertical amid the ruins"; "he sat bolt upright")

Similarity of adj decumbent

1 sense of decumbent

Sense 1
accumbent, decumbent, recumbent -- (lying down; in a position of comfort or rest)
       => unerect (vs. erect) -- (not upright in position or posture)