The branch of linguistics and logic concerned with meaning. There are a number of branches and subbranches of semantics, including formal semantics, which studies the logical aspects of meaning, such as sense, reference, implication, and logical form, lexical semantics, which studies word meanings and word relations, and conceptual semantics, which studies the cognitive structure of meaning.

the meaning of a word, phrase, sentence, or text.

plural noun: semantics

"such quibbling over semantics may seem petty stuff".

 The study of meanings in a language:

Syntax describes the rules by which words can be combined into sentences, while semantics describes what they mean.

It focuses on the study of meanings of words as well as other parts of the languages.

 

2.    Semantic is used to describe things that deal with the meanings of words and sentences.( Collins dictionary).

3.    In Linguistics is pertaining to, or arising from the different meanings of words or other symbols. (Wordreference.com) 

My concept of semantics: In linguistics it is what allows us to understand the meaning that we express through everyday language.

Techopedia: the idea of semantics is that the linguistic representations or symbols support logical outcomes, as a set of words and phrases signify ideas to both humans and machines.

My definition: It's related to the realm of meanings from the minimum expression. It is related to the interpretation and meaning of words. It is associated with the meaning of words.

 

2. Linguistic semantics studies the encoding of meaning in the context of linguistic expressions. It can be divided into structural semantics and lexical semantics.

3. Semantics allows segmenting the meaning of words, and differentiating words with similar meanings and words with opposite meanings.

4. Definition in my own words

Semantics interprets the words we want to say or write, allows us to differentiate similar words with opposite meaning.

[uncountable] (linguistics)

1.     The study of the meanings of words and phrases.

2.     The meaning of words, phrases, or systems.

noun [ U ]

UK  /sɪˈmæn.tɪks/ US  /səˈmæn.t̬ɪks/

Syntax describes the rules by which words can be combined into sentences, while semantics describes what they mean.

1: the study of meanings:

a: the historical and psychological study and the classification of changes in the signification of words or forms viewed as factors in linguistic development

(2): a branch of semiotics dealing with the relations between signs and what they refer to and including theories of denotation, extension, naming, and truth

3
a: the meaning or relationship of meanings of a sign or set of signs
especially : connotative meaning

b: the language used (as in advertising or political propaganda) to achieve a desired effect on an audience especially through the use of words with novel or dual meanings
*Cambridge dictionary:
the study of meanings in a language:

Syntax describes the rules by which words can be combined into sentences, while semantics describes what they mean.
*vocabulary.com:
Semantics is the study of meaning in language. It can be applied to entire texts or to single words. For example, "destination" and "last stop" technically mean the same thing, but students of semantics analyze their subtle shades of meaning.

Semantics:
​The study of the meanings of words and phrases.