is teams a irregular plural noun
If you still need it is a irregular noun, this is from Khan Academy
An irregular noun is a noun that becomes plural by changing its spelling in other ways than adding an “s” or “es” to the end of the word.
"teams" is plural but not irregular
www.chompchomp.com/terms.htm —> Noun
Yes, the word "teams" is an example of an irregular plural noun. Most plural nouns in English are formed by simply adding an -s or -es to the end of the singular noun. However, irregular plural nouns do not follow this pattern and instead have unique spelling changes.
To determine if a noun is irregular, you can typically refer to a dictionary or a trusted grammar resource. Most dictionaries will provide the plural form of the noun if it is irregular. If you don't have access to a dictionary, you can try searching online for resources that list irregular plural nouns.
In the case of "teams," you can see that the plural form is formed by adding -s to the end of the singular noun "team." Other examples of irregular plural nouns include "children" (singular: child), "mice" (singular: mouse), and "sheep" (unchanged from singular to plural).