Definition - What does Intramuscular mean?
Intramuscular (IM) is a modifier used to describe an anatomical location within a muscle. The term intramuscular is often used to describe injections which must be administered into the tissue of a muscle. Some medications are administered via IM injection in order to speed the delivery of the substance to the bloodstream.
SureHire explains Intramuscular
While the term intramuscular is most often used to distinguish injections into muscle tissue from those delivered into fatty tissue (subcutaneous) or directly into a vein (intravenous), the term may be used to describe anything related to muscle tissue. Thus, fatty deposits around and in the muscle tissue are referred to as intramuscular fat. Cysts and lesions may also be referred to as intramuscular to identify their nature and location.