invaluable
/ɪnˈvælju(ə)bl̩/adjective
So useful or precious that its worth cannot be measured.
Example sentences
- “Her advice proved invaluable during the move.”
- “The old maps were invaluable to the researchers studying the coastline.”
Means extremely valuable, not the opposite. The 'in-' here does not negate, a trap this word shares with 'inflammable'.