The term 'heart of the matter' is used to refer to the most important or essential part of something. The crossword solutions for this term include CORE (4 letters), GIST (4 letters), CRUX (4 letters), PITH (4 letters), NUB (3 letters), ATOM (4 letters), ATOMS (5 letters), MEAT (4 letters), ESSENCE (7 letters), STRIKETHREE (11 letters), and MIDDLEOFTHEDAY (14 letters). Each of these words can be used to describe the central point of a situation, idea, or argument. CORE, GIST, CRUX, PITH, NUB, ATOM, and ATOMS all refer to the smallest or most basic element of something, while MEAT, ESSENCE, STRIKETHREE, and MIDDLEOFTHEDAY all refer to the most important or essential part of something.