Branches of linguistics. Synchronic vs diachronic approaches to the language study. Lexicology – ‘the science of the word’

The semantic structure of a word is an organised system comprising all meanings and shades of meanings that a particular sound complex can assume in different contexts together with emotional, stylistic and other connotations.
Polysemy in diachronic terms implies that a word may retain its previous meaning and at the same time acquire one or several new ones. The main question of diachronic approach is which meaning came first, e.g.
table, n. ‘a flat slab of stone or wood’ (primary meaning); ‘a piece of furniture’, ‘the food put on the table’, ‘people seated at a table’ (secondary meanings).
Synchronically polysemy is understood as co-existence of various meanings of the same word at a certain historical period and the arrangement of these meanings in the semantic structure of a word. Synchronic typology of meaning is concerned with the opposition of main and derived meanings.
Types of polysemy:
Radial polysemy is the type of polysemy in which the primary meaning of a word stands in the centre and the secondary meanings proceed out of it like rays; each secondary meaning can be traced to the primary meaning.
Chain polysemy is the type of polysemy in which the secondary meanings of a word develop like a chain. In such cases it may be difficult to trace some meanings to the primary one.
Radical-chain (mixed) polysemy is a combination of radial polysemy and chain polysemy. Here the configuration of a diagram depends on the word’s semantic structure, hence there is a great variety of diagrams illustrating this type of polysemy.
28. Homonyms. Classifications and sources of homonyms.
Homonymy (Gr. homos ‘same’ + onyma, dial. form of onoma ‘name’) is the sameness of form combined with the difference in meaning.
Homonyms are two or more words identical in sound-form or / and spelling but different in meaning and distribution, e.g. hole, n – whole, adj; need, n – knead, v; polish, n – Polish, adj, etc.
Oxford English Dictionary registers 2540 homonyms, of which 89% are monosyllabic words and 9,1% are disyllabic