The Morphology of English

"The term morphology has been taken over from biology where it is used to denote the study of the forms of plants and animals. . . . It was first used for linguistic purposes in 1859 by the German linguist August Schleicher (Salmon 2000), to refer to the study of the form of words. In present-day linguistics, the term morphology refers to the study of the internal structure of words, and of the systematic form-meaning correspondences between words. . . .

"The notion systematic in the definition of morphology given above is important. For instance, we might observe a form difference and a corresponding meaning difference between the English noun ear and the verb hear. However, this pattern is not systematic: there are no similar word pairs, and we cannot form new English verbs by adding h- to a noun. There is no possible verb to heye with the meaning to see derived from the noun eye. Therefore, such pairs of words are of no relevance to morphology."
(Geert E. Booij, An Introduction to Linguistic Morphology, 3rd ed., Oxford University Press, 2012)
The Aims of Morphology
"Morphology is an essential subfield of linguistics. Generally, it aims to describe the structures of words and patterns of word formation in a language. Specifically, it aims to (i) pin down the principles for relating the form and meaning of morphological expressions, (ii) explain how the morphological units are integrated and the resulting formations interpreted, and (iii) show how morphological units are organized in the lexicon in terms of affinity and contrast. The study of morphology uncovers the lexical resources of language, helps speakers to acquire the skills of using them creatively, and consequently express their thoughts and emotions with eloquence."