UPTO

Up to

In mathematics, the phrase up to indicates that its grammatical object is some equivalence class, to be regarded as a single entity, or disregarded as a single entity. If this object is a class of transformations, it implies the equivalence of objects one of which is the image of the other under such a transformation.

The above text is a snippet from Wikipedia: Up to
and as such is available under the Creative Commons Attribution/Share-Alike License.

Need help with a clue?
Try your search in the crossword dictionary!