IPA: /ɪnˈvæljuːəblnəs/
KK: /ɪnˈvæljuːəblnəs/
The quality of being extremely valuable or priceless.
The invaluableness of her advice helped me make the right decision.
Invaluableness → It is formed from "in-" (meaning not), "valuable" (from Latin "valere", meaning to be strong or worth), and "-ness" (meaning the state of being). The word describes the state of being not just valuable, but beyond value, indicating something that cannot be measured in terms of worth.
Think of 'not' ('in-') being combined with 'worth' ('valuable') and the state of being ('-ness') to remember that 'invaluableness' means something that is beyond measure in worth.