A Level English Language Website
What is the difference between a phoneme and a morpheme?
PHONEME The term phoneme refers to a segment of sound that is used to distinguish the meanings of words in a particular language.
Example: In English the sounds the sounds /b/ and /m/ are distinct phonemes. (Conventionally a phoneme is written between slant lines.) How do we know? We know that if you substitute /p/ for /b/ you change the meaning of the word. For instance, 'bat' and 'mat', 'rib' and 'rim' etc., are words with different meanings.
Note that phonemes are not the same as letters in the writing system (cf. 'lap' and 'lapp' (native of Lapland) , which are spelled differently but pronounced the same) and the 'ough' sequences in 'cough' and 'bough' which are spelled the same but pronounced differently.
MORPHEME The term 'morpheme' refers to the smallest linguistic unit that carries some sort of meaning or is used to indicate that a word has some particular grammatical function. For instance, the word 'uneventful' has three morphemes un- 'not', 'event' and '-ful' and the word 'pets' has two, namely 'pet' and 'plural', which is indicated by '-s'
To find out more read:-
Crystal, D.1991 The Cambridge Encyclopedia of Language. Cambridge: Cambridge University Press