The term BIG SHARK can be broken down into two crossword solutions, MAKO and 4 letters. MAKO is a species of mackerel shark found in temperate and tropical waters around the world. It is known for its speed and agility, and is one of the fastest sharks in the ocean. The 4 letters refer to the scientific name of the species, Isurus oxyrinchus. This species is also known as the shortfin mako shark or blue pointer.