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By Madison Dresler · Jul 2026

Theory

OriginEnglish word name from Greek
Meaning"idea, speculation"
GenderGirl
Also a boy's nameShow me Theory as a boy's name

About Theory

The name Theory peaked for girls at #6092 in 2025. Theory is occasionally used for boys in 2025.

Theory in blog posts

Last Names First: Science hero surnames
The Craziest Baby Names in America

Theory on more lists

Two Syllable Names for Girls
6 Letter Girl Names
Names Ending in Y for Girls
Names That Mean Name
Names that end in y

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