The intense development of homonymy in the English language is obviously due not to one single factor but to several interrelated causes, such as the monosyllabic character of English and its analytic structure.
The abundance of homonyms is also closely connected with such a characteristic feature of the English language as the phonetic identity of word and stem or, in other words, the predominance of free forms among the most frequent roots. It is quite obvious that if the frequency of words stands in some inverse relationship to their length, the monosyllabic words will be the most frequent. Moreover, as the most frequent words are also highly polysemantic, it is only natural that they develop meanings which in the course of time may deviate very far from the central one. When the intermediate links fall out, some of these new meanings lose all connections with the rest of the structure and start a separate existence. The phenomenon is known as disintegration or split of polysemy.
Different causes by which homonymy may be brought about are subdivided into two main groups:
1) homonymy through convergent sound development, when two or three words of different origin accidentally coincide in sound; and
2) homonymy developed from polysemy through divergent sense development. Both may be combined with loss of endings and other morphological processes.
In Old English the words zesund 'healthy' and sund 'swimming' were separate words both in form and in meaning. In the course of time they have changed their meaning and phonetic form, and the latter accidentally coincided: OE sund>ModE sound 'strait'; OE зesund>ModE sound 'healthy'. The group was joined also accidentally by the noun sound 'what is or may be heard' with the corresponding verb that developed from French and ultimately from the Latin word sonus, and the verb sound 'to measure the depth' of dubious etymology. The coincidence is purely accidental.
Two different Latin verbs: cadere 'to fall' and capere 'to hold' are the respective sources of the homonyms case1 'instance of thing's occurring' and case2 'a box'. Indeed, case1<OFr cas < Lat casus 'fall', and case2<Old Northern French casse<Lat capsa. Homonymy of this type is universally recognised. The other type is open to discussion. V.I. Abayev accepts as homonymy only instances of etymologically different words. Everything else in his opinion is polysemy. Many other scholars do not agree with V.I. Abayev and insist on the semantic and structural criteria for distinguishing homonymy from polysemy.
Unlike the homonyms case and sound all the homonyms of the box group due to disintegration or split of polysemy are etymologically connected. The sameness of form is not accidental but based on genetic relationship. They are all derived from one another and are all ultimately traced to the Latin buxus. "The Concise Oxford Dictionary" has five entries for box: box1 n 'a kind of small evergreen shrub'; box2 n 'receptacle made of wood, cardboard, metal, etc. and usually provided with a lid'; box3 v 'to put into a box'; box4 n 'slap with the hand on the ear'; box5 v - a sport term meaning 'to fight with fists in padded gloves'.
Such homonyms may be partly derived from one another but their common point of origin lies beyond the limits of the English language. In these words with the appearance of a new meaning, very different from the previous one, the semantic structure of the parent word splits. The new meaning receives a separate existence and starts a new semantic structure of its own. Hence the term disintegration or split of polysemy.
It must be noted, however, that though the number of examples in which a process of this sort could be observed is considerable, it is difficult to establish exact criteria by which disintegration of polysemy could be detected. The whole concept is based on stating whether there is any connection between the meanings or not.1 Whereas in the examples dealing with phonetic convergence, i.e. when we said that case1 and case2 are different words because they differ in origin, we had definite linguistic criteria to go by; in the case of disintegration of polysemy there are none to guide us, we can only rely on intuition and individual linguistic experience. For a trained linguist the number of unrelated homonyms will be much smaller than for an uneducated person. The knowledge of etymology and cognate languages will always help to supply the missing links. It is easier, for instance, to see the connection between beam 'a ray of light' and beam 'the metallic structural part of a building' if one knows the original meaning of the word, i.e. 'tree' (OE beam||Germ Baum), and is used to observe similar metaphoric transfers in other words. The connection is also more obvious if one is able to notice the same element in such compound names of trees as hornbeam, whitebeam, etc.
The conclusion, therefore, is that in diachronic treatment the only rigorous criterion is that of etymology observed in explanatory dictionaries of the English language where words are separated according to their origin, as in match1 'a piece of inflammable material you strike fire with' (from OFr mesche, Fr mèche) and match2 (from OE gemæcca 'fellow').
It is interesting to note that out of 2540 homonyms listed in "The Oxford English Dictionary" only 7% are due to disintegration of polysemy, all the others are etymologically different. One must, however, keep in mind that patterned homonymy is here practically disregarded.
This underestimation of regular patterned homonymy tends to produce a false impression. Actually the homonymy of nouns and verbs due to the processes of loss of endings on the one hand and conversion
1 See p. 192 where a formal procedure is suggested.
on the other is one of the most prominent features of present-day English. The process has been analysed in detail in the chapter on conversion. It may be combined with semantic changes as in the pair long a : : long v. The explanation is that when it seems long before something comes to you, you long for it (long a<OE 1апz, lonz a <OE lanzian v), so that me lonzs means 'it seems long to me'.
The opposite process of morphemic addition can also result in homonymy. This process is chiefly due to independent word-formation with the same affix or to the homonymy of derivational and functional affixes. The suffix -er forms several words with the same stem: trail - trailer1 'a creeping plant' : : trailer2 'a caravan', i.e. 'a vehicle drawn along by another vehicle'.
In summing up this diachronic analysis of homonymy it should be emphasised that there are two ways by which homonyms come into being, namely convergent development of sound form and divergent development of meaning (see table below).
The first may consist in
(a) phonetic change only,
(b) phonetic change combined with loss of affixes,
(c) independent formation from homonymous bases by means of homonymous affixes.
The second, that is divergent development of meaning may be
(a) limited within one lexico-grammatical class of words,
(b) combined with difference in lexico-grammatical class and therefore difference in grammatical functions and distribution,
(c) based on independent formation from the same base by homonymous morphemes.