What is the difference between Tooth and Teeth?

There is no big difference between teeth and a tooth. Both words are referring to the same thing, but the major difference is that tooth is the singular form of whatever it represents, while teeth is the plural for the word 'tooth.' In fact, a plural word of this form is classified as an irregular plural. The tooth is the right English word for a hard, calcareous structure that is present in the mouth of most vertebrate animals.

Another difference between the two is that you can't use the two interchangeably in a sentence. The usage of one must agree with other words in a sentence; this means you will not use a tooth when you are supposed to use teeth. Teeth are important structures in the mouth, especially when biting and chewing certain food materials. Most vertebrate animals do not have the same set of teeth; in fact, the arrangement of teeth in most animals differ.