gra ‧ tu ‧ i ‧ ty /ɡrəˈtjuːəti, ɡrəˈtjuːɪti $ -ˈtuː-/ BrE AmE noun ( plural gratuities ) [countable] formal
1 . a small gift of money given to someone for a service they provided SYN tip
2 . especially British English a large gift of money given to someone when they leave their job, especially in the army, navy etc