tion sion ssion cion cian

Whenever I get talking to a teacher about spelling, I offer them my brilliant idea that every school should, in the first couple of weeks of the first term, have a "-tion Day" when each first year student and teacher will adopt a useful word ending in -tion. By the end of the day they will know what it means, how to say it naturally, say it for spelling, and, of course, spell it accurately.

I always end that conversation by saying something like, "I know there are other ways to spell the "shun" (or "zhun") ending, but <tion> is by far the most common." I've been making that assertion based on experience rather than research so thought I'd dig a little deeper to back up my claims.

If you like finding word patterns, then you probably know morewords.com or thefreedictionary.com I usually get to them by searching for something like "words ending in" or "words starting". This time I got a huge list and scooped off just over 700 I thought would be the most common, put them in alphabetical order and sorted them by <tion>, <sion>, <ssion>, <cion> and all the rest.

A year later, thanks to this tweet, I've had another look at that list, added <cian> words and removed words like 'opinion' or 'onion' that don't have /shun/ or zhun/. Then I've had a little look at how students might sort and remember the rest.

As always, memory is required for spelling but we can also play the odds a little.



83% of the time, when you hear /shun/ or /zhun/ in this list, the spelling is <tion>. On that basis, you don't really have to do much sorting and looking for patterns unless you really want to and your students find it helpful.

  • ┬áif you hear /ayshun/ then write <ation>.
  • ┬ároots that end <t>: attract/attraction etc but that doesn't account for all of them because of abolish/abolition.
  • absorb/absorption - subscribe/subscription - describe/description - all reflect a shift in pronunciation from /b/ to /p/. Again - better to just think of them as the 'norm' with a <tion> spelling.

Instead of trying to sort the 83% spelt <tion>, let's look at the remaining 17% - around 120 words with their various spelling options. I've left some words with "no obvious (to me) pattern". If you can find (or already know) a useful pattern for those words, please share @spelling_thing. The Twitter link is below. A pattern is different from a rule or an etymological fact.


is about jobs music/musician, optic/optician - even more fun if you're working with someone called Ian.


largely have roots that end <ss> impress/impression


There are still only two common words with this spellin: suspicion and coercion. So learn those two words and exclude <cion> from the list of options.


This is where you might have to use more memory but there are some good patterns.

  • listening fo /zhun/ rather than /shun/ helps.
  • if the verb is spelt with a split digraph plus <d> then it's <sion>. Lots are accounted for with this pattern. collide/collision
  • also if it ends in <d> by itself. These ones sound like /shun/. apprehend/apprehension
  • roots ending <vert> invert/inversion. It might be easier just to hang all those words on one familiar one: version.
  • likewise, any word ending <vision>: revison, television
  • a handful of roots ending /r/ or /l/ with no vowel added adhere/adhesion, compel/compulsion
  • roots ending with the sounds /s/ or /z/ when no vowel is added. precise/precision, transfuse/transfusion.
  • "No vowel added" means we have confuse/confusion (no vowel added) but accuse/accusation (vowel added).


Please don't teach these as rules. Instead, use the information to have a look at the 62 words that end <sion> and ask your students what will help them remember. Is it listening for /zhun/? Is it thinking of the root? Is it both? Is it something else?

Trying to recall rules isn't a great use of memory. Instead, try to see and remember patterns.

Here's the revised pdf: tion sion ssion cian etc 709 words