Antonyms of adj harebrained

1 sense of harebrained

Sense 1
harebrained, insane, mad -- (very foolish; "harebrained ideas"; "took insane risks behind the wheel"; "a completely mad scheme to build a bridge between two mountains")

INDIRECT (VIA foolish) -> wise -- (having or prompted by wisdom or discernment; "a wise leader"; "a wise and perceptive comment")

Similarity of adj harebrained

1 sense of harebrained

Sense 1
harebrained, insane, mad -- (very foolish; "harebrained ideas"; "took insane risks behind the wheel"; "a completely mad scheme to build a bridge between two mountains")
       => foolish (vs. wise) -- (devoid of good sense or judgment; "foolish remarks"; "a foolish decision")