Inestimable is an adjective that means too valuable to be measured or calculated.

The root word of the our word of the day is estimate. It comes from the Latin word aestimare (eye ess team ARE ay) which means ‘to appraise’ or ‘determine.’ When we say something is inestimable, we say its value is too great to be determined.

For example: Amy’s contribution to the firm has been inestimable. We can’t begin to determine how much value her expertise and hard work have brought to us.