Origin: bef. 900; ME, OE
upriht (c. G
aufrecht).
See up, right 
Related forms: uprightly, adverb
uprightness, noun
Synonyms:
1. plumb. Upright, erect, vertical, perpendicular imply that something is in the posture of being straight upward, not leaning. That which is upright is in a position corresponding to that of a person standing up: a decaying tree no longer standing upright; an upright piano. Erect emphasizes the straightness of position or posture: proud and erect; A flagpole stands erect. Vertical suggests upward direction, esp. along the shortest line from the earth to a level above it: the vertical edge of a door; ornamented by vertical lines. Perpendicular, a term frequently interchangeable with vertical, is used esp. in mathematics: the perpendicular side of a right triangle; to erect a perpendicular line from the base of a figure. 3. honorable. 6. pole, prop, pier, pile, column.
Antonyms:
1. leaning, horizontal.