Which term is abbreviated as SQ?

The term abbreviated as SQ stands for subcutaneous. This refers to the method of administering medication by injecting it into the fatty tissue just beneath the skin. Subcutaneous injections are commonly used for vaccines and medications like insulin, allowing for slow absorption into the bloodstream.

The other options represent different routes of medication administration: "by mouth" refers to oral administration, "per rectum" pertains to rectal administration, and "sublingual" involves placing a medication under the tongue for quick absorption. Each of these methods has distinct uses and implications, but the correct choice focuses specifically on the subcutaneous route.