Informal :: Informal (a.) 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..
Informal :: Informal (a.) Deranged in mind; out of one's senses.
Informality :: Informality (n.) The state of being informal; want of regular, prescribed, or customary form; as, the informality of legal proceedings..
Informality :: Informality (n.) An informal, unconventional, or unofficial act or proceeding; something which is not in proper or prescribed form or does not conform to the established rule..