immeasurable

Immeasurable means too vast or too deep to put a number on. Not simply large — beyond the reach of measuring at all.

The word attaches itself to things nobody would try to count: immeasurable harm, immeasurable relief, an immeasurable debt to somebody who helped you. That is where its force comes from, and why it works badly on physical quantities, since almost anything physical can in fact be measured. The neighbouring word incalculable does the same job with a slightly more arithmetical flavour. Note the shape of it: measurable with im- in front, the same pattern as impossible.