Vocabulary of a language as a System

between words
Classifications of vocabulary units

changing requirements and conditions of human communication and cultural and

other needs.
Language – constantly developing but systematic whole.
Groupings of words within vocabulary are the result of the analysis of various relations between words.

words – new notions constantly come into being, requiring new

names for them.
Newly coined word or phrase or a new meaning for an existing word, or a word borrowed from another language.

given language
Sources of neologisms are extremely varied
It is often difficult

to state unambiguously when exactly a word stops being a neologism
Dictionaries of neologisms

lolspeek
Various coinages: to friend – to unfriend; to like –

to unlike; phablet; webinar; phoneying – pretending to be using a phone when in fact you are not

I'm indulging in a tweetup - that is, a meetup

for tweeps (a contraction of "twitter peeps", itself a contraction of "Twitter people").
If I can't drag myself away from this particular social media service for even a moment, I may be a borderline twitterholic - although my fluency in speaking twitterese will be hard to dispute by anyone else in the twittersphere. I may even win the approval of the elite twitterati, so long as I don't embarrass myself by sending dweeps (drunken tweets)”.

meanings of words;
Equivalence – implies full similarity of meaning of

two or more language units. Extremely rare in case of separate words. Could be observed more regularly in case of phrases;
Opposition – the contrast of semantic features.

meaning, common paradigm, the same substituting elements and possible characteristic

set of suffixes rendering the lexico-grammatical meaning

(for animals);
Abstract nouns;
Material nouns;
Object nouns;
Proper names for people;
Toponymic names

dog-days, dogcart etc.

sound, and characterized by semantic polarity of their denotational meaning.
Types

of antonyms can be distinguished according to the character of semantic opposition.

characterized by different degrees of the same property. Always imply

comparison: large/little – small; young – old;
Complemetaries/Contradictories – based on binary opposition; include only two members: dead – alive;
Conversives – words denoting one and the same referent as viewed from different points of view: to buy – to sell; to give – to recieve

– ugly
Derivational antonyms: appear – disappear; pleasant - unpleasant

concept.
Members of the semantic field are not synonymous components,

but are joined together by some common semantic component – common denominator of meaning (e.g.: concept of kinship, concept of colour, parts of human body).

verbs (extend, spread, span); adfectives (spacious, roomy, vast, broad).

within the framework of the sentence and reflecting the existing

link between things and event in reality.
Contextual associations are formed as a result of regular co-occurrence of words in similar repeatedly used contexts.

TAXI;
SUNSHINE – BRIGHTLY – BLUE – SKY
Thematic groups are independent

of classification into parts of speech.

– car; bus; taxi
Horse – animal
Table – furniture
Hyponymic relationship exists

between the meaning of the general and the individual terms.

as distinguished from names of the species – hyponyms:
E.g.: animal

(hyperonym) – wolf, dog, mouse (hyponym)
Some words may be both hyponyms and hyperonyms:
Animal – Dog – bulldog; bloodhound; collie; Alsatian