The plural of mouse is mice.
A small rodent with a pointed snout, small rounded ears, a body-length scaly tail and small black eyes.
The plural of "mouse" when referring to the rodent species is "mice". This is an irregular plural, as it does not follow the common rule of adding -s or -es to the end of a singular noun to make it plural.
In general, when a noun ends in -s, -x, -z, -sh, -ch or -o, we add -es to make it plural. With the word "mouse" we don't follow this rule, it is irregular noun.
The word "mouse" has its origins in the Old English language, where it was spelled "mūs."
It's likely that the irregular plural form "mice" developed because it was already in use in Old English, when the word was first borrowed into the language.
As the language evolved, the inflected forms of nouns were simplified, and many nouns lost their distinct plural forms. However, some irregular forms like the "mice" persisted, even as the singular forms became "mouse".
This is not unique to the word mouse, there are many other irregular nouns in English which preserve their old plural forms and don't follow the rule of adding -s to make them plural.
Here are a few sentences that illustrate the difference between "mouse" (singular) and "mice" (plural) when referring to the rodent:
Another fun fact about mice is that they are great jumpers, they can jump up to a foot high, about 8 to 12 inches, which is quite remarkable considering their small size. This is an adaptation that allows them to quickly escape from predators.