IPA: //ˈbækˌbrɛkɪŋ//
KK: /ˈbækˌbrɛkɪŋ/
Very difficult and tiring, requiring a lot of physical effort.
The workers faced backbreaking labor in the hot sun all day.
Comparative: more backbreaking
Superlative: most backbreaking
Backbreaking → It is formed from "back" (from Old English "bæce", meaning the rear part of the body) and "breaking" (from Old English "brecan", meaning to break). The word describes something that is so physically demanding it feels as if it could break one's back.
Think of the 'back' as the rear part of the body and 'breaking' as the act of breaking — backbreaking means something that is so hard it feels like it could break your back.