IPA: /ʌnˈtʃeɪndʒɪŋnəs/
KK: /ʌnˈtʃeɪndʒɪŋnəs/
The quality of not changing or remaining the same over time.
The unchangingness of the landscape made it feel timeless.
Unchangingness → It is formed from "un-" (meaning not), "changing" (from the root "change" which comes from Old French *changier*, meaning to exchange or alter), and "-ness" (meaning the state of being). The word "unchangingness" refers to the state of not changing or remaining constant.
Think of 'not' ('un-') changing ('changing') and the '-ness' indicating a state. This helps you remember that unchangingness means the state of not changing.