The flag and cap badge feature Mercury (Latin: Mercurius), the winged messenger of the gods, who is referred to by members of the corps as "Jimmy". The origins of this nickname are unclear. According to one explanation, the badge is referred to as "Jimmy" because the image of Mercury was based on the late mediaeval bronze statue by the Italian sculptor Giambologna, and shortening over time reduced the name Giambologna to "Jimmy". The most widely accepted theory of where the name Jimmy comes from is a Royal Signals boxer, called Jimmy Emblem, who was the British Army Champion in 1924 and represented the Royal Corps of Signals from 1921 to 1924. It is one of the eight chalk hill figure military badges carved at Fovant, Wiltshire. It is the latest one to be made, as it was placed in 1970 following the Corp's 50th anniversary. The corps are also nicknamed 'Interflora's' due to close resemblance of the symbols.
The Corps motto is "certa cito", often translated from Latin as Swift and Sure, although it actually translates from Latin as "fixed quickly" . It is easily seen on any of the Corps Badges.