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>, <cian>, <ssion>, <cion> and <sion>.

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


According to my list, 83% of the time, when you hear /shun/ or /zhun/, 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.

  •  if you hear /ayshun/ then write <ation>.
  •  roots 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/. In a simple spelling lesson it's better to just think of them as the 'norm' with a <tion> spelling With your more confident spellers, you can go deeper through word study or by looking at phonetics and pronunciation. For unconfident spellers, that kind of study is likely to be a barrier to learning.

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 only two common words with this spelling: 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 for /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 with  /r/ or /l/ with no vowel added. adhere/adhesion (as opposed to adore/adoration) 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 pdf: tion-sion-ssion-cian-etc-word-list