home w Arthur Shuraev watermelon wa⋅ter⋅mel⋅on [waw-ter-mel-uhn] –noun 1. the large, roundish or elongated fruit of a trailing vine, Citrullus lanata, of the gourd family, having a hard, green rind and a sweet, juicy, usually pink or red pulp. 2. the vine itself. a b c d e f g h i j k l m n o p q r s t u v w x y z wait warpath waiting wall wash washing-machine washer waterfall watermelon waterproof weather water-canon wei-wou