- The word synchronise is often shortened to a single syllable which sounds like sink, but whose spelling varies between <sync> and <synch>. This variability introduces us to a simple question: what information should a spelling contain?

- Figure 1 shows that the spelling <sync> has been more common over the last fifty years but <synch> lingers on as a minority variant with roughly the same proportion of usage.
Spellings should represent the sound of a word
- Most obviously, a spelling should represent the sound of the word, /sɪŋk/. This narrows it down to the following possibilities: <sink>, a word which already exists, <sinc>, <sinck>, <sinq>, <sincq>, <sinch>, <synk>, <sync>, <synch>, and perhaps <cink>, <cinq>, <cync> etc. Other spellings would not give us enough of a clue about how to read the word. If it were spelt, say, <snk>, we should not know if it sounded like sank or sink, or sunk, etc. And if it were spelt, like, <xkcd>, then we could never reconstruct /sɪŋk/ from those letters.
Spellings should represent the meaning of a word
- The next criterion is that a word should be spelt like words it is related to. This narrows the list down to just <sync> and <synch>, as both of these spellings can be found by truncating the parent form <synchronise>. The net effect of this pattern is that words with similar meanings end up having similar spellings.
Which spelling is better?
- We can now compare these two possible forms. At first it seems obvious that <sync> is better than <synch> because the latter form might be rhymed with pinch or Grinch. But why does the spelling with <h> linger on as a minority variant? The answer seems to lie in the spelling demands of the inflected forms, {ing} and {ed}

- The spellings <synced> and <syncing> run into to problem that they could be rhymed with minced and mincing, because the letter <c> is pronounced as /s/ when followed by <e> or <i> (compare noticed and noticing). The spellings <synched> and <synching> are thus used a lot more than the base form <sync>, as can be seen from the graphs below. Even though they could be rhymed with pinched and pinching, they at least have the benefit of not introducing any new ambiguities.

- There are very few words (that I know of) which show a distribution like this. One example is the American spelling <catalog> which sometimes has the British <u> in its {ing} and {ed} forms. Hence <catalog(u)ed> and <catalog(u)ing>. And another example is miked, miking, short for microphone. Again, the base form mic is more common than mike but the spellings <miced> and <micing> are clearly unacceptable.
- Anyone know more examples?