Injected

Injected is the past tense and past participle of the verb inject, meaning to introduce a substance, material, or signal into something else. It is used as an adjective to describe something that has had a substance introduced by injection, or in passive constructions such as “the vaccine was injected.” The word derives from Latin injicere, from in- meaning into and jacere or facilitative forms meaning to throw.

In medicine and veterinary practice, injections are a common method for delivering drugs, vaccines, and other therapies. They are typically administered with a syringe and needle and can be delivered by intramuscular, subcutaneous, or intravenous routes. Safety, sterility, and correct technique are important considerations, and injections are performed by trained healthcare professionals or, in some cases, patients themselves.

In engineering and industry, injected describes substances introduced into systems or processes. For example, fuel-injected engines deliver fuel directly into the combustion chamber rather than via a carburetor. Injected fluids or gases may be used for cooling, lubrication, cleaning, reaction control, or mixing within reactors, pipelines, and other equipment.

In computing and information security, injection refers to the introduction of untrusted input into a program, query, or command, potentially enabling unauthorized actions. Code injection, SQL injection, and command injection are examples of vulnerabilities or techniques in which injected content is interpreted as code. Mitigation focuses on input validation, escaping or parameterization of interfaces, and least-privilege execution to prevent harmful effects.

Etymologically, injected comes from Latin injicere, formed from in- meaning into and jacere meaning to throw.