Antonyms of adj straight-backed

1 sense of straight-backed

Sense 1
straight-backed -- (having a straight back; "a straight-backed wooden chair"; "a slim straight-backed dancer")

INDIRECT (VIA backed) -> backless -- (lacking a back; "a stool is a backless and armless seat")

Similarity of adj straight-backed

1 sense of straight-backed

Sense 1
straight-backed -- (having a straight back; "a straight-backed wooden chair"; "a slim straight-backed dancer")
       => backed (vs. backless) -- (having a back or backing, usually of a specified type)

Synonyms of adv straight-backed

1 sense of straight-backed

Sense 1
erectly, straight-backed -- (in a straight-backed manner; "the old man still walks erectly")