The term 'let out' can be defined as to RELEASE or set free. This can be done in a variety of ways, as evidenced by the crossword solutions. The solutions include 'EXTEND' (6 letters), 'WIDENED' (7 letters), 'EMIT' (4 letters), 'RENT' (4 letters), 'VENT' (4 letters), 'FREED' (5 letters), 'unpen' (5 letters), 'WIDEN' (5 letters), 'LEASED' (6 letters), 'DISMISS' (7 letters), 'exhaled' (7 letters), 'pourout' (7 letters), 'RELEASE' (7 letters), 'UNLEASH' (7 letters), 'ELONGATE' (8 letters), and 'recessed' (8 letters). All of these words describe different ways of releasing something, whether it is a physical object, an emotion, or a sound.