Coinage/neologism - The deliberate creation of a new word. This is not a common process of word formation. E.g. widgit, spoof, hobbit

Compounding - Words are combined together to form new words. These can be open, hyphenated or solid.

Clipping - Words are shortened and the shortened form becomes the norm.

Acronym - First letters are taken from a series of words to create a new word.

Initialism - The first letters are taken from a series of words, but each letter is pronounced.

Affixation - one or more free morphemes are combined with one or more bound morphemes.

Lexical Conversion - A word shifts from one word class to another.

Eponym - Names of a person or company are used to define particular objects. Often they are the inventors of the object.

Back formation - A verb is created from an existing noun by removing the suffix.

Generalisation/broadening - the meaning of old words broadens so that it retains its old meaning but also takes on new meanings to become polysemous. E.g. Holiday originally from holy day

Specialisation/narrowing - a word becomes more specific in meaning e.g. meat, which used to be all food

Amelioration - Over time words acquire a more positive meaning e.g. pretty, which used to mean sly.

Pejoration - Over time a word acquires a more negative meaning e.g. villain used to mean farmer

Weakening/bleaching - The loss of reduction of the force of the meaning of a word. E.g. thing used to be a meeting

Metaphor - Words acquire additional meanings as physical ideas are extended to abstract ideas.

Euphemism - The creation of polite and roundabout expressions for unpleasant words. E.g. downsizing, when jobs are made redundant.

Polysemy - Words acquire meanings that coexist with the original. E.g. milking it. It has evolved from the verb to milk in its original sense.

Some words have silent letters, for example, knight and palm

Some words are spelt the same but sound different (homographs), for example the verb 'read' in both present and past tense.

Some words are spelt differently but sound the same (homophones) for example sew/so and through/threw

Noah Webster's mission was to establish a model of American English that was equal, if not superior to British English. He set out to 'ascertain the true principles of the language... to purity it from some palpable errors and reduce the number of anomalies' (1832).

However, language purists counter this, arguing that removing it is yet another example of dumbing down language. They view this as a form of linguistic decay.