In linguistics, syncope is the deletion of phonemes from a word, or from a phrase treated as a unit; compare elision. more...
Syncope gives rise to many of the silent letters in English spelling. The traditional spellings of English place names such as Worcester and Gloucester bear evidence of syncope, as does the usual pronunciation of parliament. Syncope is the reason why Australian English is colloquially known as Strine.
In some traditional English spellings, the syncope suffered by abbreviated forms is indicated by an apostrophe, as in didn't and I'd've. In other, similar words, it is customary to omit the apostrophe, as in gonna for going to or wannabe for want to be. The forms showing syncope, whether indicated or not, are usually marked as colloquial and not used in the most formal sorts of English.
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