ˈhemə̇ˌstik noun
Etymology: Latin hemistichium, from Greek hēmistichion, from hēmi- hemi- (I) + stichos line, verse + -ion -ium; akin to Greek steichein to go — more at stair
: half a poetic line usually divided by a caesura (as a metrically independent colon or group of feet of less than regular length)