Allomorph

From Teflpedia

An allomorph (/ælə(ʊ)mɔ:f/) is a differing form, either spoken or written, of a single morpheme.

Morpheme Written or spoken? Notes
plural -s both Pronounced three different ways
third person -s Both Pronounced three different ways
genitive 's Both Pronounced three different ways
-ed Both Can be pronounced 3 different ways, and also written -t.

etc