A selective service class denoting that the registrant is already a reserve member of the armed forces or a student taking military training, as in ROTC or an accepted aviation cadet applicant.

(medicine) Once per day, used for prescription directions.

(music) A subgenre of hardcore punk.

(medicine) A small protein fragment present in the blood after a blood clot is degraded by fibrinolysis, used in the diagnosis of deep vein thrombosis, pulmonary embolism, etc.

plural of D lock

A lock shaped like an elongated letter D, used to secure an unattended bicycle to railings etc.

Dolce and Gabbana

(Internet slang) A habitual poster on the /d/ - Hentai/Alternative board on 4chan; a member of the /d/ community.

(modal, auxiliary verb, colloquial) Had best.

plural of D-dimer