General:
* Injector: A more neutral term, often used in medical settings.
* Needle: While not a complete synonym, the needle is a crucial component of the syringe.
* Hypodermic: A more formal and technical term, referring to the injection of substances under the skin.
Informal:
* Shot: This term is common in everyday language when referring to an injection.
* Jab: A casual term for an injection, sometimes used humorously.
Specific contexts:
* Pipette: Used for transferring small volumes of liquids in scientific research.
* Baster: A kitchen tool used for injecting liquid into food.
The best word to use will depend on the specific situation and the intended audience.