noun
kiddo
KIH-doh
noun
1
An informal, friendly way to address a child or a younger person, often used affectionately even with adults.
"Nice job out there, kiddo."
"Hang in there, kiddo, it gets easier."
How to Use Kiddo
Learner’s notesIn plain EnglishA warm, casual way to call someone "kid," often used between friends or by an older person to a younger one.
When to use it
Very informal and affectionate — common in spoken English, rare in formal writing.
Common pairings
hey kiddo
good job, kiddo
Word Forms
kiddos plural, kiddoes plural
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Etymology
From "kid" + the informal suffix "-o," found in similar casual coinages like "cheerio."