1. immature or inexperienced: a callow youth.
2. (of a young bird) featherless; unfledged.
3. a recently hatched worker ant.
1. untried, green, raw; naive, puerile, jejune.
1. mature, adult, experienced.
Origin: before 1000; Middle English, Old English calu bald; cognate with Dutch kaal, German kahl bald, OCS golŭ bare
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