Formal:
* Phlebotomy: This is the most common synonym for venipuncture. It refers to the practice of drawing blood.
* Blood draw: This is a more general term that encompasses any method of drawing blood.
* Venous blood collection: This is a more specific term that describes the process of collecting blood from a vein.
Informal:
* Blood test: This is the most common informal term for venipuncture.
* Stick: This is a slang term used by healthcare professionals.
The best word to use will depend on the context.