What Is the Plural of Basis?

Can you form the plural of the word basis without scratching your head and turning to Google? Many Americans, including native speakers, may sometimes find themselves wondering about how to refer to more than one basis.

In this brief review, we’ll establish the correct way to write the plural of basis, as well as how to find the plural version of other similar words.

The Meaning of the Word Basis

The word basis indicates the base, principle, or standard of something. For example, you could say that voting is the basis of democracy, or that common values are the basis of good friendships.

Most people probably won’t struggle with this word in its singular form. The spelling challenge enters when we have more than one basis for something. For instance, what if you want to talk about a basis for your scientific theory, then another, and then a third?

The Plural of Basis Is Bases

The plural version of basis is bases, pronounced BAY-seez and different from the plural of base (e.g., the runner ran the bases after hitting a home run). This follows the convention of pluralizing “-is” words into “-es” endings. Other examples include:

thesis > theses

synopsis > synopses

analysis > analyses

Even those with developed spelling and grammar skills might occasionally pause at such variations. This is because basis and similar words don’t follow more-typical formulas, such as simply adding an “-s” or “-es” to the end of a singular word:

cat > cats

speaker > speakers

box > boxes

If we applied standard plural endings to thesis, synopsis, and analysis, we would have thesises, synopsises, and analysises—all incorrect in addition to being difficult to pronounce.

Why Some Words Are Hard to Pluralize

At this point, you know the plural of basis is bases. Why is it that some words are trickier to make plural?

The issues stem from two separate causes. The first is that many words you find in American English have their roots in other languages and places. So, one word might be pluralized according to an older English tradition, while others might draw from French, German, Greek, Spanish, or even Arabic. Our language imports and assimilates new words and phrases all the time, and many maintain their own rules for spelling and sound.

Speaking of sound, the second cause for pluralization issues with some words is that following normal guidelines would make them problematic to pronounce. In fact, that’s why so many words ending with “-s” have distinctive ways of turning into plurals.

You now have your basis for spelling correctly!

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