1. unfastened - Adjective
2. unfastened - Verb
affording unobstructed entrance and exit; not shut or closed
not tied
not buttoned
not closed or secured
Source: WordNetan open door Source: Internet
they left the door open Source: Internet
the wind picked up the hem of her unbuttoned coat Source: Internet
the car door was unfastened Source: Internet
unfastened seatbelts Source: Internet
Cautions may be displayed for special problems (fuel low, check engine, tire pressure low, door ajar, seat belt unfastened). Source: Internet