adjective | KAL-oh
Callow is a synonym of immature used to describe someone,
especially a young person, who does not have much experience and does not know
how to behave like an adult. Like the word immature, callow is often used
disapprovingly.
This meaning of callow links
the word directly to its origin, the Old English word calu, meaning “bald,” and
to today’s more common use in describing someone possessed of youthful naiveté.
Calu eventually fledged
into callow with the same “bald, hairless” meaning, but was applied to bald
land too—that is, land denuded of vegetation or not producing it in the first
place.
By the 16th century, callow had expanded beyond the literal
sense of “lacking hair or flora” to its avian use of “lacking feathers” as well
as to today’s familiar application to people. Callow now is most often used to
suggest the inexperience or immaturity of young people brimming with confidence
but still, figuratively, unfledged.