What we are talking about when it comes to usage of the terms morpheme, morph and allomorph is usually innately related to linguistic science, respectively the study of human and other communication systems.
However, one might also be concerned with the fact that the hierarchical term of which morpheme, morph and allomorph are sub-branches, namely Morphology, was firstly introduced by Johann Wolfgang von Goethe (1749 - 1832) to describe the study of forms in nature and the evolution of those forms in order to meet higher standards.
Although the implied meaning of the term morphology, which is the study of forms, hasn't changed within the process of transferring it to make it usable in linguistic sciences, the knowledge that lies beneath it had undergone several changes to make it fit the linguistic needs more appropriately.
In linguistic science, Morphology approaches to, since there is no uniform definition of "word", define words as structural units which are composed of at least one base morpheme and one or more additional or decomposable morphemes (Study Guide Morphology, Antje Lahne,).
Our following assignment will focus on allomorph specifically.
B.CONTEXT:
I. Definition:
An allomorph is “any of the different forms of a morpheme”. [Richard, Platt &Weber, 1987: 9]
E.g. In English, the inflectional noun plural morpheme {S1} is often shown in writing by adding –(e)s to the end of a singular noun, e.g. cat /kæt/ →cats /kæts/. Sometimes this morpheme is pronounced /-z/, e.g. dog /dɒɡz/, and sometimes it is pronounced /-ɪz/, e.g. box /bɒks/ → boxes /bɒ ksɪz/. Ii is believed that /-s/, /-z/, /ɪz/ are three allomorphs of the inflectional noun plural morpheme {S} because: They are in complementary distribution: /-s/ occurs only after the voiceless consonants /p, t, k, f, Ɵ/. /-ɪz / occurs only after the sibilant consonants /s, z, ʃ, ʒ, ʤ, ʧ/. /-z/ occurs after voiced sounds, including all vowels and voiced consonants except /z/,