Antonyms of adj twelve-sided

1 sense of twelve-sided

Sense 1
twelve-sided -- (having twelve sides)

INDIRECT (VIA multilateral) -> unilateral, one-sided -- (involving only one part or side; "unilateral paralysis"; "a unilateral decision")

Similarity of adj twelve-sided

1 sense of twelve-sided

Sense 1
twelve-sided -- (having twelve sides)
       => multilateral (vs. unilateral), many-sided -- (having many parts or sides)