The term 'canary sound' refers to the vocalizations of canaries, which are small, songbird-like birds. The three crossword solutions for this term are 'TWEET, ' 'CHEEP, ' and 'TRILL.' A TWEET is a short, high-pitched sound that canaries make, while a CHEEP is a slightly longer, higher-pitched sound. A TRILL is a rapid series of notes that canaries produce. All of these sounds are used by canaries to communicate with each other and to attract mates.