IPA: /ˈθɛnsˌfɔrwərd/
KK: /θɛnˈsɪfɔrd/
From that time or place onward; continuing from a specific point in time or location.
The rules were changed, and thenceforward, everyone had to follow the new guidelines.
Thenceforward is formed from "thence" (from Old English "þænne", meaning from that place) and "forward" (from Old English "forweard", meaning toward the front or in the direction of). The word "thenceforward" means from that place onward or from that time onward.
Imagine starting from a specific place ('thence') and moving 'toward the front' ('forward') — that's how you remember that 'thenceforward' means from that place onward.