The term 'Tide Descriptor' refers to a type of tide that is characterized by its low and high points. The crossword solution for this term is 'NEAP, ' which is an acronym for 'Near Minimum Water Level.' This type of tide occurs twice a month, when the sun and moon are at right angles to each other in relation to the Earth. During this time, the gravitational pull of the sun and moon cancel each other out, resulting in lower than average tidal ranges.