STYLISTIC FUNCTIONS OF LITERARY (HIGH-FLOWN) WORDS
Literary words of the English language can be classified into the following groups: poetic diction, archaic words, barbarisms and foreign words, bookish (learned) words.
Poetic diction.
Poetic words are stylistically marked, they form a lexico-stylistic paradigm. In the 17th-18th centuries they were widely used in poetry as synonyms of neutral words. In modern poetry such a vocabulary barely exists.
Poetic words are diverse; they include: і) archaic words (commix - mix)
2) 
archaic forms (vale - valley)
3) 
historic words (argosy - large merchant ship)
4) 
poetic words proper (anarch, brine),
Their main function is to mark the text in which they are used as poetic, thus distinguishing it from non-fiction texts. In modern poetry such words are seldom used. Their stylistic meaning gets more vivid when they are contrasted to neutral words.
Archaic words.
Archaic words, i.e. out-dated words that denote existing objects, are divided into two groups:
a) archaic words proper: words which are no longer recognised in modern English. They 
were used in Old English and have either dropped out of language use entirely or completely changed (troth - faith, losel - worthless);
b) archaic forms of the words: corse instead of corpse, an instead of and, annoy instead of annoyance.
Speaking of archaic words we should distinguish "ageing/newness" of the word form and "ageing/newness" of the denotatum. And then, accordingly, we may correlate archaic words and historic words on the one hand as well as lexical and stylistic neologisms on the other.
Lexical neologisms are new words that denote new objects (laser, shopping, pop promo, killer, satellite). Stylistic neologisms are new names that denote already existing objects and notions (mole - a spy who successfully infiltrates an organisation; ageism - discrimination of a person on the ground of age).
Historical words are associated with definite stages in the development of a society and cannot be neglected, though the things and phenomena to which they refer no longer exist. Historical words (yeoman, thane, baldric, goblet) have no synonyms as compared to archaic words which may be replaced by their modern synonyms.
Historical words and lexical neologisms having no stylistic meaning, do not form lexico-stylistic paradigms. But archaic words and stylistic neologisms mark the text stylistically, distinguishing it from neutral speech.
In fiction, together with historical words, archaisms create the effect of antiquity, providing a true-to-life historical background and reminding the reader of past habits, customs, clothes etc. The usage of archaisms, incompatible with conversational words, might in some cases lead to a humorous or satirical effect.
Barbarisms and foreign words.
There are many borrowings in every language, some of them being assimilated. We may distinguish four groups of such words in English: foreign words, barbarisms, exotic words, and borrowings.
Foreign words are close to barbarisms, but they are characterised by occasional usage only, mainly in literary speech. They do not form a lexico-stylistic paradigm, though they may be used to create some stylistic effect.
Barbarisms are words of foreign origin which have not been entirely assimilated into the English language preserving their former spelling and pronunciation. Most of them (e.g. chic, chagrin, en passant) have corresponding English synonyms.
Exotic words are borrowed foreign words denoting objects characteristic of a certain country (canzonet, matador). They have no synonyms in the language-borrower, do not form a lexico-stylistic paradigm and therefore are not considered to be lexical EM, but nevertheless they may be used for stylistic purposes.
Borrowings, if they are assimilated, do not differ much from native words as far as their stylistic aspect is concerned. They are usually high-flown synonyms of neutral native words (to commence — to begin, labour- work, female - woman).
The stylistic functions of barbarisms and foreign words are similar, they are used to create a local colouring, to identify a personage as a foreigner, or to show his/her mannerism.
Bookish (learned) words are mostly used in official or high-flown style (catenate, depicture, disimprove, dalliance). In official usage, they mark the text as belonging to this or that style of written speech, but when used in colloquial speech or in informal situations, they may create a comical effect.
3.2. STYLISTIC FUNCTIONS OF CONVERSATIONAL (LOW-FLOWN) WORDS.
Here we refer colloquial words, general slang words (interjargon), special slang words (social and professional jargons), dialectal words and vulgarisms. Some linguists differentiate slang and jargon, but the difference is vague and is practically irrelevant for stylistics. Generally, colloquial words according to their usage may be divided into three big groups:
1) literary colloquial,
2) familiar colloquial:
3) low colloquial.
According to the relations between their form and meaning, all colloquial words may be divided into three subgroups:
a) words which are based on the change of their phonetic or morphological form without changing their lexical and stylistic meaning:
b) words which are the result of the change of both their form and lexico-stylistic meaning;
c) words which resulted from the change of their lexical and/or lexico-stylistic meaning without changing their form.
The first subgroup comprises such varieties of word-form change as:
a) clipping (shortening): serge - sergeant, caff - cafeteria;
b) contamination of a word combination: leggo - let's go, kinda - kind of, c'mon - come on; [gimme, dunno, gonna, wanna]
c) contamination of grammatical forms: I'd go, there's, we're going.
These words have no lexico-stylistic paradigms. They possess denotative meaning only. Within the second group of colloquialisms, we may distinguish two varieties of the word-form change leading to the alteration of its lexico-stylistic meaning:
a) the change of the grammatical form which brings the change of the lexico-stylistic meaning: heaps - very many, a handful — a person causing a lot of trouble;
b) the change of the word-building pattern which causes the emergence of another lexico-stylistic meaning through:
— affixation: oldie, tenner, clippie;
— compounding: backroom boy, dip-joint:
— conversion: to bag, teach-in;
— telescopy: swellegant, flush, fruice;
— shortening and affixation: Archie (Archibald);
— compounding and affixation: strap-hanger, arty-crafty,
Ail these words form a iexico-stylistic paradigm as they have synonyms among neutral and literary words and are characterised by various connotations while giving additional characteristics to the denotatum.
The third subgroup of colloquial words is the most numerous and comprises: a) words with emotive-expressive meaning only: oh, bach, ah as well as word combinations having a special expressive function: / never, Good (Great) heavens, God forbid; b; words and word combinations having both connotative and denotative meaning where the former one prevails: terribly, you don't say so, did he really;
c) words in which denotative and connotative meanings interplay: bunny — a waitress, colt-team - young team;
d) words in which denotative meaning in certain contextual conditions gives rise to a new connotative meaning: affair - business, to have an affair- to be in love, beggar - poor person, lucky beggar- lucky person;
e) • words denotative and connotative meanings of which are completely different from
their former meanings: chanter (poetic) - a singer; chanter (col.) - a person who sells horses at the market.
Slang is composed of highly colloquial words whose expressiveness and novelty make them emphatic and emotive as compared to their neutral synonyms.
We can distinguish two varieties of slang: general slang (interjargon) and special slangs (social as well as professional jargons). Some of the former slangisms may enter the colloquial or even the neutral layer of the vocabulary (phone, flu, sky-scraper). Novelty is the most impressive feature of slang. As it disappears, they lose their expressiveness.
Vulgarisms are the words which are not generally used in public. However, they can be found in modern literature nowadays, though formerly they were tabooed or marked by the initial letters only.
Dialectal words ('ud - would, 'im - him, 'aseen - have seen, canna - cannot, dinna-don't, sportin - sporting) are used to intensify the emotive and expressive colouring of speech which is primarily determined by the peculiarities of social or geographical environment.
Conversational words of all kinds are widely used for stylistic purposes. There are four speech spheres in which they are mostly largely used: everyday speech, newspaper language, poetry, and fiction.
In newspaper language, colloquial words and word combinations, and sometimes general slang words, are used to give an expressive evaluation of facts and events. In modern poetry, words of all layers are most widely used. Lyrical poetry allows the usage of various non-poetic words to create the atmosphere of sincerity, confidence etc. Slang words in fiction (mostly in dialogues) add to the informality and emotiveness of the character's speech alongside with indicating social and speech peculiarities of the personages.