I. ˈpentə̇ˌgän, -tēˌ- sometimes -tə̇gən or -tēg- noun
( -s )
Etymology: Late Latin pentagonum, from Greek pentagōnon, from neuter of pentagōnos five-angled, from penta- + -gōnos (from gōnia angle) — more at -gon
: a polygon having five sides — see area table
II. adjective
Usage: usually capitalized
Etymology: from the Pentagon, pentagonal building (erected 1943) in Arlington Va., that is the headquarters of the United States Dept. of Defense and other government offices
: of or relating to the Pentagon building especially as symbolizing the United States military, naval, and air force leadership concentrated there