Language Tips

Spelling tip of the week – commission

© Macmillan
Liz Potter
Written by Liz Potter

In this weekly post, we bring more useful content from the Macmillan Dictionary to English language learners. In this series of spelling tips we will be looking at some of the most commonly misspelled words in English and suggesting ways to improve your spelling.

This week’s tip looks at a word that is very frequently misspelled in searches of Macmillan Dictionary: commission.



Words with double consonants often catch people out, and two frequent failed searches in lookups of Macmillan Dictionary are the forms *comission and *commision. 

Let’s deal with them in turn. The reason commission has two ms is because it is derived from the verb commit. This in turn was formed from the Latin prefix ‘cum’ meaning ‘with’ and the verb ‘mittere’ meaning to put or send. The etymology is not important, but the Latin bit is, because as Michael Rundell points out in his spelling guide, words of Latin origin often have double letters in the middle, while words of Germanic origin rarely do. As a general rule, the more formal words in English – the ones associated with the law, administration, bureaucracy – have Latin roots. So knowing or guessing that a word like commission is more likely to be of Latin origin will also help you guess that the consonants in the middle are more likely to be doubled.

This general rule also applies to the other misspelling, *commision, but here the sound will also guide you. There are plenty of words in English that end in -ision – vision, collision, elision and so on – but they are all pronounced with the voiced consonant /ʒ/ not the unvoiced  /ʃ/. So if you know what the word commission sounds like, you know it can’t end -ision.

I haven’t seen any failed searches for *comision, which suggests that people are aware double consonants are involved, they’re just not sure where in the word they come. The answer in this case, as in others we will look at, is both are doubled.

You can find some information on why English spelling is so difficult, as well as helpful tips on mastering it here. You can search for other posts in this series using the tag ‘spelling tips’.

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Liz Potter

Liz Potter

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