Words and meaning
Acronym: A word formed from the initial letters of two or more successive words (e.g. UNESCO: United Nations Educational, Scientific and Cultural Organisation).
Antonym: A word with the opposite meaning to another word.
Backformation: The formation of a word from another one, from which it appears to be derived (e.g. the verb to babysit from the earlier babysitter).
Blending: Forming a new word by combining the beginning of one word with the end of another (e.g. motel from motor and hotel).
Borrowing: Introducing specific words or forms of words from one language into another (e.g. pasta from Italian into English, or weekend from English into French).
Clipping: Where a word is shortened to form a new variant (e.g. advertisement becomes ad or advert).
Coinage: The creation of new words (i.e. neologisms) in a language.
Colloquial: The casual conversation of everyday language.
Compounding: Forming a word from two or more units that are themselves words (e.g. whiteboard from white and board).
Derivation: Creating a new word from an existing word, often with the addition of a prefix or suffix (e.g. unwilling derives from will with the prefix un- and the suffix -ing).
Figurative language: Language which expands upon the basic or literal meaning of a word or phrase (e.g. simile or metaphor).
Idiom: Phrases generally understood in a language but which do not directly translate (e.g. "I caught the train by the skin of my teeth" = "I only just caught the train in time").
Intensifier: A word, often an adverb or adjective, which has little meaning by itself but is used to add force to other phrases (e.g. "really," "very").
Jargon: Words and phrases known primarily by a group of people, often within a particular profession, which enable them to exchange complex information efficiently. Jargon may be unintelligible to people outside the group who use it.
Lexis: The complete vocabulary of a language.
Neology: The process through which new words (neologisms) are formed, including acronyms, blends, compounds, and eponyms.
Semantic: Related to the meaning of words.
Semantic field: A group of words that relate to a shared area of meaning (e.g. needle, nurse, and antibiotic could be grouped within the semantic field of medicine).