Not formal or ceremonious. / Not in accord with the usual regulations. / Suited for everyday use. / (of language) Reflecting everyday, non-ceremonious usage.

The condition of being informal.

plural of informality

plural of informalism

A word, phrase, behaviour, etc. that is informal. / An art movement based on abstract and gestural tendencies rather than definite form.

One who informs someone else about something. / A person who tells authorities about improper or illegal activity. / One who informs, animates, or inspires.

simple past tense and past participle of inform

Instructed; having knowledge of a fact or area of education. / Based on knowledge; founded on due understanding of a situation.

(obsolete) Created, given form. / (obsolete) Unformed or ill-formed; deformed; shapeless. / (astronomy, obsolete) Not included within the figures of any of the ancient constellations.

Without regular form; shapeless; ugly; deformed.