Commas before conjunctions (e.g., and, or, but). When a word like and, or, and but (called conjunctions) joins two standalone sentences, you should put a comma before it. (The real name for a standalone sentence within a longer sentence is independent clause .).Words like and, or, and but are known as conjunctions.earch. When a word like and, or, and but (called conjunctions) joins two standalone sentences, you should put a comma before it. (The real name for a standalone sentence within a longer sentence is independent clause .).
1. a polygon having five angles and five sides. 2. the Pentagon, a. a building in Arlington, Va., built in the form of a pentagon and containing most of the offices of the U.S. Department of Defense. b. the U.S. Department of Defense; the U.S. military establishment. [1560â70; < Late Latin pentagÅnum < Greek pentÃ¡gÅnon, n. use of neuter of pentÃ¡gÅnos five-angled.
Defense News (âDoD Weighs Major COCOM Realignmentâ): The Pentagon is considering a major overhaul of its geographical combatant commands, possibly realigning oversight within hot-button areas of the world and eliminating thousands of military and civilian positions, according to defense sources.