"Deflation hollows" is not a commonly used term in geology or other scientific fields. It's possible you've encountered a mispronunciation or misspelling.

Here are some possibilities for what you might be referring to:

* Deflation: This is a geological process where wind erodes and removes loose material, like sand or dust, from a surface. Deflation can create various landforms, including:

* Blowouts: Large depressions in the ground formed by deflation.

* Yardangs: Elongated, streamlined ridges sculpted by deflation.

* Desert pavements: A layer of closely packed pebbles and cobbles left behind after finer material is removed by deflation.

* Hollows: These are general terms for depressions in the ground, which could be formed by various processes, not just deflation.

If you could provide more context or a specific description of what you're looking for, I might be able to offer a more accurate answer.