Why is the 'cy' in cycle and cynic pronounced differently

Question

Consider the following example:

• Cynic → /ˈsɪn.ɪk/

• Cylinder → /ˈsɪl.ɪn.də(r)/

• Cycle → /ˈsʌɪk(ə)l/

Cynic and cylinider are stressed on first syllables yet the cy is pronounced /sɪ/ and not /saɪ/ (as in cycle).

Question: Why is the cy in cynic and cycle pronounced differently?

Can anyone offer some insight?

^{(There's a similar question here but that does not answer my question)}

Answer 1

“Cynic” ends in the suffix -ic. There is a sort of rule (although it has quite a lot of exceptions) that the stressed syllable in words ending in the suffix -ic is pronounced with a short vowel sound when it’s spelled with a single vowel letter followed by at least one consonant letter.

The word cycle ends in -cle. This is not a suffix, and there aren’t clear rules about the pronunciation of words ending in these letters, but speaking in terms of more general patterns, the absence of consonant doubling can be said to make a long value a possibility for a single vowel letter before -cle. Compare the use of a long vowel (diphthong) in Bible, title, and idle versus a short vowel in dribble, little and riddle.

Cycle is spelled with a single c after the y because the Ancient Greek source word κύκλος has a single kappa after the upsilon.

Answer 2

The creation of English dictionaries in the 18th and 19th centuries generally normalized and stabilized spelling for words in the spoken language.   Lexicographers used etymology to inform the rules they applied.   The point here is that pronunciation and spelling have a relationship that is more correlation than causation.

Others have mentioned prosody as a reason why we pronounce "cynic" and "cycle" differently.   I suspect that the words in English also continue to reflect distinctions in the original Greek words κυνικός (cynic) and κύκλος (cycle).   There are (at least) two import differences:   (1) the first syllable is stressed in one and not the other and (2) the "consonant" after the vowel in question is voiced in cynic but not cycle (both in Greek and in English).

English vowel sounds change dramatically depending on whether the following consonant sound is voiced or voiceless.   This is most apparent in short pairs like "bad" vs. "bat" where we pronounce the vowel before the voiced d much longer than before the voiceless t.   In IPA, we write these sounds as [æː] and [æ], respectively.

So my answer (or guess, really) is that English patterns for differentiating vowels based on following consonants caused the preservation of distinctions in the original Greek.