IPA: /ˈkæloʊ/
KK: /ˈkæl.oʊ/
Not having much experience or maturity; often used to describe someone who is young and naive.
The callow youth made several mistakes during his first job.
Callow originates from the Old English word 'ceald' (meaning cold) and 'weard' (meaning guardian or keeper). The word 'callow' refers to someone who is inexperienced or immature, akin to a young bird that is still without feathers and thus vulnerable to the cold.
Think of a young bird that is 'cold' and 'unprotected' — that's why 'callow' means inexperienced or immature.