Answer
Strad is the colloquial term used for Stradivari's instruments. It is an abbreviation of Stradivarius, which is the Latinized form of Stradivari's surname. The term Strad is used to refer to any string instrument made by Stradivari or his workshop, including violins, violas, cellos, and double basses. Strads are considered to be among the finest string instruments ever made, and they are highly prized by musicians and collectors.