Babyhood is the earliest period of a person's life, from birth until around age two or three, when someone is still a baby. During babyhood, children learn foundational skills like sitting up, crawling, walking, and saying their first words. They depend completely on parents or caregivers for everything: food, comfort, safety, and love.

Parents often look back on their children's babyhood with mixed feelings. Those years involve sleepless nights, constant diaper changes, and exhausting days, but they also bring incredible moments: first smiles, first steps, first words. Babies change so rapidly during this time that parents sometimes joke they blink and suddenly their infant has become a toddler.

The word describes both a stage of development and a quality of being. When someone says “she's barely out of babyhood,” they mean the person is still very young, perhaps two or three years old. Writers sometimes use babyhood to talk about the early stages of anything: “the babyhood of aviation” means when airplanes were brand new and people were just learning to fly them.