invaluable
/ɪnˈvælju(ə)bl̩/ adjective C1- Having great or incalculable value.
From the library
“I regard them as invaluable.”
This invaluable friend was a very young woman, and very lately married.
“My dear fellow, you have been invaluable to me in this as in many other cases, and I beg that you will forgive me if I have seemed to play a trick upon you.
He has given me an extra pair of eyes upon a very active pair of feet, and both have been invaluable.”
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