Informal
Pronunciation : In*form"al
Part of Speech : a.
Etymology : [Pref. in- not + formal.]
Definition : 1. Not in the regular, usual, or established form; not according to official, conventional, prescribed, or customary forms or rules; irregular; hence, without ceremony; as, an informal writting, proceeding, or visit.
2. Deranged in mind; out of one's senses. [Obs.] These poor informal women. Shak.
Source : Webster's Unabridged Dictionary, 1913