The term 'Arrow Cousin' is a reference to the game of darts, which is a popular pub game in which players throw small missiles, or darts, at a circular target. The term 'Arrow Cousin' refers to the fact that darts are similar to arrows, and thus can be considered cousins of arrows. The crossword solution for this term is 'DART, ' which is a four-letter word that accurately describes the game of darts.