Chasmal is an adjective that describes a deep, wide, and often frighteningly large opening or gap. It is derived from the Latin word 'chasma, ' which means 'gaping void.' The crossword solutions for this term are OPEN (4 letters), CAVERNOUS (9 letters), and GAPING (6 letters). All three words describe a large opening or gap, with OPEN referring to a space that is not blocked off, CAVERNOUS referring to a large, dark, and often underground space, and GAPING referring to an opening that is wide and deep.