Apheresis (especially if vowel). Is the phoneme removed from the beginning of a word?
Example. Speakers may shorten about time to 'bout time.
Syncope. Is the sound removed from the middle of a word?
Example. The Luiseño word hunwutumi 'the bears' is pronounced /hunwutmi/. Speakers syncopate the third /u/.
Apocope. Is the phoneme removed from the end of a word?
Example. The word thumb lost its final /b/ over time.