Homonyms. Synonyms. Antonyms

Homonyms
words identical in sound and spelling or, at least, in one of these aspects, but different in their meaning
bank, n. — a shore
bank, n. — an institution for receiving, lending, exchanging, and safeguarding money
ball, n.—a sphere; any spherical body
ball, n. — a large dancing party

Origin and Function
homonyms are accidental and, therefore, purposeless. In the process of communication, they are more of an encumbrance, resulting in confusion or misunderstanding.
Yet, they underpin popular humour (pun).

Pun
a joke based on the play on words of the similar form but different meaning (i. e. on homonyms) as in the following

Types of Homonyms

Homonyms Proper
words identical in sound and spelling

Homophones
Words identical in sound but different in spelling:
night, n.—knight, n.; piece, n. —peace, n.; scent, n.— cent, n.—sent, v. (past indef., past part, of to send);
rite, n.— to write, v.—right, adj.;
sea, n.—to see, v.—C [si:] (the name of a letter).

Homographs
words identical in spelling but different in sound:
to bow [bau], v.— to incline the head or body in salutation
bow [bou], n. — a flexible strip of wood for propelling arrows
to lead [li:d], v. — to conduct on the way, go before to show the way
lead [led], n. — a heavy, rather soft metal

SOURCES OF HOMONYMS
phonetic changes
borrowings
word-building
split polysemy

Phonetic Changes
in the course of their historical development, two or more words formerly pronounced differently may develop identical sound forms and thus become homonyms:
Night and knight were not homonyms in Old English as the initial k in the second word was pronounced, and not dropped as it is in its modern sound form: O. E. kniht (cf. O. E. niht).
A more complicated change of form brought together another pair of homonyms: to knead (O. E. cnedan) and to need (O. E. neodian).
In Old English the verb to write had the form writan, and the adjective right had the forms reht, riht.

Borrowings
A borrowed word may, in the final stage of its phonetic adaptation, duplicate in form either a native word or another borrowing: in the group of homonyms rite, n. — to write, v. — right, adj. the second and third words are of native origin whereas rite is a Latin borrowing (< Lat. ritus).

Word-Building
conversion
shortening
sound-imitation (onomatopoeia)

Conversion
the most important type in these terms. Such pairs of words as comb, n.— to comb, v., pale, adj.— to pale, v., to make, v. — make, n. are numerous in the vocabulary.
Homonyms of this type, which are the same in sound and spelling but amount to o different categories of parts of speech, are lexico-grammatical homonyms.

Shortening
type of word-building which adds the number of homonyms.
fan, n. in the sense of "an enthusiastic admirer of some kind of sport or of an actor, singer, etc." is a shortening produced from fanatic.
Its homonym fan, n. is a Latin borrowing which denotes a device for waving lightly to produce a cool current of air.

Onomatopoeia
forms pairs of homonyms with other words: e. g. bang, n. ("a loud, sudden, explosive noise") — bang, n. ("a fringe of hair combed over the forehead").

Common Features of the Sources of Homonymy
In onomatopoeia and shortening, the pairs or triples of words homonyms have purely incidental similarity.
Conversion, however, is an exception, for, one word of the pair is produced from the other:
a find < to find.)

Split Polysemy
Two or more homonyms can originate from different meanings of the same word when, for some reason, the semantic structure of the word breaks into several parts.

Reasons of the Split Polysemy
the semantic structure of a polysemantic word is a system, within which all its constituent meanings are held together by logical associations
In most cases, the semantic unity of all meanings is conditioned by one of the meanings (e.g. the meaning "flame" in the noun fire).
If this meaning drops out from the word semantic structure, associations between the rest of the meanings may no longer hold, the semantic structure loses its unity and falls into two or more parts that then are viewed as independent lexical units.

Split Synonymy (board – n.)
board, n.—a long and thin piece of timber
board, n.—daily meals, esp. as provided for pay, e. g. room and board
board, n.—an official group of persons who direct or supervise some activity, e. g. a board of directors

Nowadays, however, the item of furniture, on which meals are served and round which boards of directors meet, is no longer denoted by the word board but by the French Norman borrowing table, and board in this meaning, though still registered by some dictionaries, can very well be marked as archaic as it is no longer used in common speech. Consequently, the semantic structure of board was split into three units.

Lexico-Grammatical
Typology of Homonyms
homonyms may amount to both the same and different parts of speech.
Obviously, the classification of homonyms is underpinned by this distinctive feature.
Also, the paradigm of each word should be considered, since the paradigms of some homonyms coincide completely, and that of others only partially.

Types of Homonyms

Full Lexical Homonyms
Words of the same part of speech with an identical paradigm:
match, n. — a game, a contest;
match, n.—a short piece of wood used for producing fire

Partial Lexical Homonyms
words of the same part of speech identical only in their corresponding forms:
to lie (lay, lain), v. to lie (lied, lied), v.
to hang (hung, hung), v. to hang (hanged, hanged), v.
to can (canned, canned) (I) can (could)

Simple Lexico-Grammatical Partial Homonyms
words of the same part of speech. Their paradigms have one identical form, but it is never the same form:
(to), found, v. - found, v. (past indef., past part, of to find)
to lay, v. - lay, v. (past indef. of to lie)
to bound, v. - bound, v. (past indef., past part. of to bind)

Complex Lexico-Grammatical Partial Homonyms
words of different parts of speech with one identical form in their paradigms.
rose, n. - rose, v. (past indef. of to rise)
maid, n. - made, v. (past indef., past part. of to make)
left, adj. - left, v. (past indef., past part, of to leave)

SYNONYMS: ARE THEIR MEANINGS THE SAME OR DIFFERENT?
"I have always liked you very much, I admire your talent, but, forgive me, — I could never love you as a wife should love her husband."
(From The Shivering Sands by V. Halt)
Though they all render more or less the same feeling of liking, each of the three verbs describes it in its own way: "I like you, i. e. I have certain warm feelings towards you, but they are not strong enough for me to describe them as "love" — so that like and love are in a way opposed to each other.

In terms of component analysis, synonyms may be defined as words with the same denotation, or the same denotative component, but differing in connotations, or in connotative components.
A group of synonyms may be studied via their dictionary definitions (definitional analysis), like in the following:
look, stare, gaze, glare, glance, peer.

Semantic Typology of Synonyms

Ideographic Synonyms
ideographic (words that render the same notion but differ in the shades of meaning):
assemble - amass, collect, convene, summon, mobilize
table – bar, bench, board, buffet, bareau, console, dresser, slab

Stylistic Synonyms
stylistic (words that differ in terms of their usage in functional styles):
assemble – convene, gather; bunch, flock, huddle; gang up, hang around;
good – favourable, acceptable, reputable; delux, first-class, super; bully, bad, crack, rad, sick.

Absolute Synonyms
absolute (identical in their shades of meaning and in all their stylistic features):
articulation, pronunciation, verbalization
However, absolute synonyms are rare in vocabulary and, at the diachronic level, the phenomenon of absolute synonymy is anomalous and consequently temporary: the vocabulary system invariably tends to eliminate it either via abolishing one of the absolute synonyms or by developing semantic or contextual differentiation in one or both (or all) of them.

Antonyms
words of the same part of speech with contrasting meanings: hot — cold,
light — dark, happiness — sorrow, to accept — to reject, up — down.

If synonyms form whole, often numerous, groups, antonyms are usually believed to appear in the counterpart pairs. For instance, the adjective cold has warm for its antonym, and sorrow may be contrasted with gaiety.
On the other hand, a polysemantic word may have an antonym (or several antonyms) for each of its meanings. So, the adjective dull has the antonyms
for its meaning "deficient in interest“: interesting, amusing, entertaining,
for its meaning "deficient in intellect“: clever, bright, capable
for its meaning "deficient in activity“: active etc.