/ ˈsemisɜːkl; NAmE -sɜːrkl/ noun
1.
( geometry ) one half of a circle
—picture at circle
2.
the line that forms the edge of a semicircle
3.
a thing, or a group of people or things, shaped like a semicircle :
a semicircle of chairs
We sat in a semicircle round the fire.
► semi·cir·cu·lar / ˌsemiˈsɜːkjələ(r); NAmE -ˈsɜːrk-/ adjective :
a semicircular driveway
••
WORD ORIGIN
early 16th cent.: from Latin semicirculus (see semi- , circle ).