Take a dive' is an idiom that means to suddenly decrease in value or quality. The crossword solutions for this term are PLUMMET (7 letters), PLUNGE (6 letters), SCUBA (5 letters), TRIP (4 letters), DROP (4 letters), LOSE (4 letters), LIEDOWN (7 letters), and LIESDOWN (8 letters). All of these words can be used to describe a sudden decrease in value or quality, such as plummeting from the sky, plunging into the water, taking a scuba diving TRIP, dropping something, losing something, lying down, or lying down flat.