Entry 1 sense Webster, 1913 Aftermath /ăf'-tẽrm-ăthˌ/ · Aft·er·math · IPA /ˈæf.tɚˌmæθ/ 01 n. A second moving; the grass which grows after the first crop of hay in the same season; rowen. 1. A second moving; the grass which grows after the first crop of hay in the same season; rowen.