The term 'Canal Buildup' refers to the process of constructing a canal, which is a man-made waterway used for transportation, irrigation, or other purposes. The crossword solution for this term is 'EARWAX, ' which is a yellowish waxy substance secreted in the ear canal of humans and other mammals. EARWAX helps protect the ear from dust, dirt, and other foreign particles, and it also helps keep the ear canal lubricated.