IPA: /ɪkˈstrimnəs/
KK: /ɪkˈstrimnɪs/
The quality or state of being very different from the usual or average; a high degree of something.
The extremeness of the weather made it difficult for people to go outside.
Extremeness is formed from "extreme" (from Latin "extremus", meaning outermost or farthest) and the suffix "-ness" (meaning the state or quality of). The word "extremeness" refers to the state or quality of being extreme or at the outer limits.
Think of 'extreme' as being at the 'outermost' point, and '-ness' indicating a state. This helps you remember that 'extremeness' refers to the quality of being at the outer limits.