י

That’s a Hebrew letter yod. It’s a sort of joke.

So, yod coalescence is a thing that even has its own page on Wikipædia. No-one says ‘action’ as ‘ac-tee-on’, though some may say ‘question’ as ‘kwes-tee-on.’ True, dat. Many people say ‘duke’ as ‘jook,’ though also many say it as ‘dook.’ These are all instances of yod coalescence, which is a pronunciation feature of some people that converts consonants into other consonants when they are written before ‘e’ or ‘i’ (and the tense sound of ‘u’ counts as ‘i-oo’ for this purpose), like this: ‘d’ → ‘j,’ ‘s’ → ‘sh,’ ‘t’ → ‘ch’ or ‘sh’ and ‘z’ → ‘zh.’

Examples are ‘duke,’ ‘fission,’ ‘christian,’ ‘action,’ ‘fusion’ which become, if you like, ‘jook,’ ‘fishon,’ ‘chrischan,’ ‘acshon,’ ‘fuzhon.’ The problem is knowing where to stop. I’m sure some people do say ‘chrischan,’ though a lot more probably say ‘chris-tee-an’. Even more may alternate between the 2, without being aware of it much.

The one certainty is that no-one says ‘ac-tee-on’. Let’s commit! The rule will be yod coalescence everywhere. It’s weird! It has to be done! After ‘dh,’ ‘z,’ ‘gh,’ and ‘zh’ as described above, probably no-one will even notice.