It could be called a pet name, or a nickname(although nicknames are not always related to the real name).
More technically, the use of this kind of shortening between friends is termed hypocorism.
abbreviation
The word bizz is the shortened form of the word business.
'Jas' is a shortened form of 'Jasper'. The complete word may be a personal proper name for a male. It traces its origins back to the Hebrew word for a kind of quartz.
"Chat" is a shortened form of the word "chatter" which is from a middle English word meaning "to talk rapidly".
Bedlam
It means a word that is accompanied by "is" in a shortened form. Ex. He's in the kitchen.
A contraction.
Cap
The word bizz is the shortened form of the word business.
a shortened form of a word or phrase. such as 'n' = noun. 'Adj' = adjective
The word Piano is a shortened form of the Italian name for the instrument Pianoforte, meaning soft and loud.
The word for a shortened form of a word is called a "contraction."
An abbreviation is a shortened form of a word or phrase.
'Flu' is just the abbreviation of 'Influenza'.In - 'Flu' - enza
some thing that progressively gets smaller
It is not shortened word so it has full form i think
Tom is a diminutive (nickname or shortened form) of Thomas and its variants.The name comes from the Aramaic word toma, meaning twin.
The girl's name with the shortened form Tina is typically Christina.