noun
use; application; where to use
Refers to the appropriate situation, timing, or purpose for using something; often implies finding the right opportunity or context.
この道具の使いどころがわからない。
I don't know when to use this tool.
彼は本当にここぞという使いどころで力を発揮する。
He really shows his strength at the crucial moment.
使い道 focuses on the way or purpose something is used, while 使いどころ emphasizes the timing or situation for its use.
Compound of 使い (use) and どころ (place, point, time), a voiced form of ところ. The exact historical derivation is straightforward.