IPA: /ˈwɔːrtaɪm/
KK: /ˈwɔrˌtaɪm/
A time when a war is happening.
Many changes occur in society during wartime.
Wartime → It is formed from "war" (from Old English *werre*, meaning conflict or battle) and "time" (from Old English *tima*, meaning a period or duration). The word "wartime" refers to a period characterized by war or conflict.
Think of a specific "period" ('time') during which there is "conflict" ('war') — that's what wartime means.