noun
kindling; firelighter
Material used to start a fire, such as small sticks, paper, or commercial fire starters.
キャンプで焚き付けに新聞紙を使った。
We used newspaper as kindling at the camp.
焚き付けが湿っていて、なかなか火がつかなかった。
The kindling was damp and wouldn't catch fire easily.
薪 refers to firewood or larger pieces of wood for sustaining a fire, while 焚き付け is specifically the smaller material used to start the fire.
Compound of 焚き (the continuative form of 焚く 'to burn, kindle') and 付け (the continuative form of 付ける 'to attach, apply'), literally 'applying to burn'.