One of the first temporary teeth of a young mammal (one of 20 in children) WordNet 3.0 & Open English WordNet

Deciduous teeth or primary teeth, also informally known as baby teeth, milk teeth, or temporary teeth, are the first set of teeth in the growth and development of humans and other diphyodonts, which include most mammals but not elephants, kangaroos, or manatees, which are polyphyodonts. Wikipedia

That fall out during the course of normal development Wikipedia Disambiguation

first set of teeth in diphyodonts Wikidata

A tooth of the first set of teeth. OmegaWiki

The first set of teeth in the growth development of humans and many other mammals. OmegaWiki

A tooth which will be replaced as a child ages, as opposed to an adult permanent tooth; a milk tooth. Wiktionary

A baby tooth or milk tooth which is replaced by later permanent teeth in animals displaying diphyodonty. Wiktionary

Any tooth of the first set of teeth of young people (or livestock). Wiktionary

Tooth of the first set of teeth. Wiktionary (translation)