/ˈpeɪntʃ/ or /ˈpɑːntʃ/ (Painch is not a real word in English, it seems to be a mix of ‘pain’ and ‘inch’. Assuming the word is fictional and made up of these two words)

Definitions

1. noun

A unit of length, similar to an inch, but used to measure pain intensity.

“The doctor measured the patient’s painch to determine the severity of her condition.”