underlook

A concealed or oblique glance.

[…] exultingly cried Lord Carhampton, stealing an underlook at Maurice O'Driscoll, whom ^([sic]) he knew was wont to boast of his Milesian lineage; […]

[…] rubbing his hands busily, rocking back and forth with one foot in front of the other, his head down but watching Watson with an underlook that was very arrogant, cocky, […]

To look up at from below; to inspect from underneath.

They would be Shepherds and feed his Sheep, and anoint them for the Scab, and underlook them.

Upon a rough table-ledge, they came to it at last; the place where they could lean in between the trees, and overlook and underlook the shining tumult [of the waterfall].

To fail to notice or give due importance to, especially because one is notionally looking too low (found in complement with overlook, as if it meant "to fail to notice because one is looking too high").

Existing review research has focused on specific terms, underlooking important developments in the area.

The CHAIRMAN. I am not overlooking anything. I am just making inquiry of you for information. Mr. THOMSON. I know you do not overlook anything. The CHAIRMAN. I am not overlooking or underlooking, but just listening to you and trying to get your viewpoint.