IPA: /ɪkˈstɛnsɪti/
KK: /ɪkˈstɛnsɪti/
The quality or state of being extended in space or size; it refers to how much space something occupies or the range of its extension.
The extensity of the universe is difficult to comprehend due to its vastness.
Extensity → It is formed from "ex-" (meaning out) and "tensio" (from Latin, meaning to stretch). The word "extensity" refers to the quality of being extended or stretched out in space.
Think of something that is 'stretched out' ('tensio') and 'going out' ('ex-') — that's why extensity means the quality of being extended.