infancy

American  

[in-fuhn-see] / ˈɪn fən si /

noun

plural

infancies

1. the state or period of being an infant; very early childhood, usually the period before being able to walk; babyhood.

2. the corresponding period in the existence of anything; very early stage.

   Space science is in its infancy.

3. infants collectively.

4. Law. the period of life to the age of majority, 21 years at common law but now usually 18; minority; nonage.

---

infancy British  

/ ˈɪnfənsɪ /

noun

1. the state or period of being an infant; childhood

2. an early stage of growth or development

3. infants collectively

4. the period of life prior to attaining legal majority (reached at 21 under common law, at 18 by statute); minority nonage

---

Etymology

Origin of infancy

From the Latin word infantia, dating back to 1485–95. See infant, -cy

Example Sentences

Leigh syndrome is a rare metabolic condition that affects the brain and muscles, usually appearing in infancy or early childhood.

From Science Daily • Mar. 31, 2026

When Ryder Paredes, 22, began studying computer science as an undergraduate three years ago, “AI was in its infancy, it wasn’t very intelligent,” the Montclair, N.J., native said.

From The Wall Street Journal • Mar. 22, 2026

Artificial intelligence may still be in its infancy, but this mainstay of the stock market rally now has investors worried it will be its downfall.

From Barron's • Feb. 4, 2026

Most of these children were born during the pandemic and spent much of their infancy quarantined indoors, their earliest socialization filtered through the blue light of tablets and television, Aguet said.

From Los Angeles Times • Jan. 27, 2026

Modern computing was in its infancy, still used only by corporations and the military, or other huge government operations.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel

Related Words

• inception