Plural of Nebula

The Quick Answer

The plural of nebula is nebulae or nebulas.

The Plural of nebula

The plural of nebula is nebulae. The alternative plural nebulas is rare but still acceptable.

Most nebulae are of vast size; some are hundreds of light-years in diameter.
In 1715, Edmond Halley published a list of six nebulas.

The noun nebula has a Greek root, which is the derivation of the plural nebulae. Nebulas (which adheres to the standard rules for forming plurals) is also an accepted plural.

Are You Good at Plurals?

Here's a quick test.

Getting ready...

The Standard Rules for Forming the Plurals

The table below shows the standard rules for forming the plurals of nouns in English.

Type	Example of Type	Forming the Plural	Plural
Most Nouns	nebula scythe	add s	nebulas scythes
Noun Ending s, sh, ch, x or z	box dress	add es	boxes dresses
Nouns ending [consonant] o	hero zero tomato	add either s or es (There are no rules for this - you have to know.)	heroes zeros tomatoes
Nouns ending [vowel] o	patio ratio	add s	patios ratios
Nouns ending [consonant] y	story penny	change the y to an i and add es	stories pennies
Nouns ending [vowel] y	donkey chimney	add s	donkeys chimneys
Nouns ending f or fe	dwarf hoof	ves and/or s (There are no rules - you have to know.)	dwarfs hooves or hoofs
Exceptions	man louse	some nouns undergo a vowel or letters change	men lice
More exceptions	salmon sheep	some nouns do not change at all	salmon sheep
Foreign rulings	nebula medium	some nouns adopt foreign rulings	nebulae media

Why Is There Confusion over the Plural of Nebula?

Confusion arises over the plural of nebula because its original plural form (nebulae) derives from Greek and native English speakers are drawn to nebulas, which adheres to the standard ruling for forming plurals.

Nebulae is by far the more common plural of the two. (See the difference in Google's Ngram Viewer.)

Another Interactive Exercise

Here are three randomly selected questions from another exercise on plurals, which can be edited, printed to create an exercise worksheet, or sent via email to friends or students.

Help Us To Improve Grammar Monster

Do you disagree with something on this page?
Did you spot a typo?

Please tell us using this form.

"Smashing Grammar" (2019)
Written by the founder of Grammar Monster, "Smashing Grammar" includes a glossary of grammar essentials (from apostrophes to zeugma) and a chapter on easily confused words (from affect/effect to whether/if). Each entry starts with a simple explanation and basic examples before moving to real-life, entertaining examples. All entries conclude with a section highlighting why the grammar point is relevant for a writer and top-level bullet points summarizing the entry. [More�]

"Grammar for Grown-ups" (2011)
Vocational rather than academic, "Grammar for Grown-ups" is packed with real-life examples and keeps you engaged with a wealth of great quotations from Homer the Greek to Homer the Simpson. Straight talking and methodical, Craig Shrives draws on his years compiling Grammar Monster and as an army officer to present a comprehensive but light-hearted and easily digestible grammar reference guide. [More�]