Antonyms of adj boastful

1 sense of boastful

Sense 1
boastful, braggart (prenominal), bragging (prenominal), braggy, big, cock-a-hoop, crowing, self-aggrandizing, self-aggrandising -- (exhibiting self-importance; "big talk")

INDIRECT (VIA proud) -> humble -- (marked by meekness or modesty; not arrogant or prideful; "a humble apology"; "essentially humble...and self-effacing, he achieved the highest formal honors and distinctions"- B.K.Malinowski)

Similarity of adj boastful

1 sense of boastful

Sense 1
boastful, braggart (prenominal), bragging (prenominal), braggy, big, cock-a-hoop, crowing, self-aggrandizing, self-aggrandising -- (exhibiting self-importance; "big talk")
       => proud (vs. humble) -- (feeling self-respect or pleasure in something by which you measure your self-worth; or being a reason for pride; "proud parents"; "proud of his accomplishments"; "a proud moment"; "proud to serve his country"; "a proud name"; "proud princes")