A wake-up call is a signal used to alert someone that it is time to wake up. The crossword solutions for the term 'wake-up call' include 'Mornin' (6 letters), 'ALARM' (5 letters), 'BUGLE' (5 letters), 'CHIRP' (5 letters), 'REVEILLE' (8 letters), and 'AROUSAL' (7 letters). These words all refer to different methods of signaling someone to wake up, such as an ALARM clock, a BUGLE call, or a bird chirping. The most well-known wake-up call is 'REVEILLE, ' which is a BUGLE call used by the military to signal the start of the day.