As a Noun:
1. A small tube with a plunger and a fine hollow needle or pointed end. It is used for putting liquids into something and taking them out, for example drugs into a person's body or for taking blood samples from them. English = syringe, hypodermic needle.
2. The act of using a syringe to put liquids into a person's body. English = injection. Informal English = jab.
3. The act of injecting someone with a weak form of a disease as a way of protecting them from it. English = immunisation, inoculation, vaccination.
4. A person who injects themselves with harmful drugs; the drugs themselves. English = drug addict, intravenous drug user; drugs, heroin.
5. A medicine made from the germs that cause a disease and which is injected into people to prevent them from getting the disease. English = vaccine.
6.
As a Verb or Adjective:
1. To use a syringe to put liquid into a person's body. English = inject. Informal English = jab.
2. To inject someone with a weak form of a disease as a way of protecting them from it. English = immunise, inoculate, vaccinate.
3. To inject yourself with harmful drugs, often because you are addicted to them. Informal English = shoot up.
4. [Especially at 'unusual' locations on the body (e.g., teeth, jaw, various joints)], to administer a local anaesthetic by injection.