Semantics is the study of meaning in language. It involves the study of sense relations and word meanings.
denotation
Denotation is the literal, dictionary definition of a word. It’s the objective meaning.
For example: winter is the coldest season of the year, between autumn and spring.
connotation
Connotations are the vibes associated with a word. For example “aroma” may have the connotation of being an exotic and special smell.
Field is broader than a domain, it is an area;
synonym
Antonymy is the relationship between words that similar meanings. But can vary with context.
antonym
Antonymy is the relationship between words that have opposite meanings. But can vary with context.
hyponym and hypernym
Hypernyms is a level above hyponym.