IPA: /rɪˈmɑːrkəblnəs/
KK: /rɪˈmɑrkəblnəs/
The quality of being very unusual or extraordinary, making something stand out.
The remarkableness of her achievements inspired everyone around her.
Remarkableness → It is formed from "remarkable" (from Latin *remarcabilis*, meaning worthy of notice) and the suffix "-ness" (meaning the state or quality of). The word "remarkableness" refers to the quality of being worthy of notice or extraordinary.
Think of something that is 'worthy of notice' — that's what 'remarkable' means, and adding '-ness' indicates the quality of being remarkable.