What does it mean when is at the end of a word?

"Is" at the end of a word usually indicates a plural form of a noun. This is especially common in Latin and Greek-derived words.

Here are some examples:

* Analysis (singular) - Analyses (plural)

* Basis (singular) - Bases (plural)

* Crisis (singular) - Crises (plural)

* Thesis (singular) - Theses (plural)

It's important to note that not all words ending in "is" are plural. Some words are simply singular, like "axis" or "oasis."

If you're unsure about the plural form of a word, it's best to consult a dictionary or online resource.