A hypocorism is a shorter or diminutive form of a word or given name, for example, when used in more intimate situations as a nickname or term of endearment.
Hypocorisms are often generated as:
-a reduction (in English) of a longer word to a single syllable, then adding -y or -ie to the end, such as movie (“moving picture”), telly (“television”) or Aussie (“Australian”‘).
-a contracted form of a given name, such as Tony from Anthony, Rosy for Rosemarie or Vicky from Victoria.
-a given name with a diminutive suffix,such as Juanita from Juana.
-ulus/-ula in Latin, most famously in the case of the Roman emperor Caligula, whose moniker means “little boot”. He received the name from soldiers in reference to the small army sandals (caligae, singular caliga) he wore when he was young. Likewise the name Ursula is derived from ursa (bear) and means “little bear”.