Refers to a small cut or indentation made on a surface, often for measurement or as a guide. Also used for the graduation marks on a ruler or scale.
I made a notch in the wood to mark it.
The marks on the ruler are so fine that they are hard to read.
Compound of 刻み (きざみ, 'cutting into small pieces') + 目 (め, 'mark'). The exact historical derivation is uncertain, but the word transparently describes a cut mark.