Sheerest

adjective

1. Very thin or transparent.

   "Her light, sheer dress caught everyone’s attention."

2. Pure in composition; unmixed; unadulterated.
3. (by extension) Downright; complete; pure.

   "I think it is sheer genius to invent such a thing."

4. Used to emphasize the amount or degree of something.

   "The army's sheer size made it impossible to resist."

5. Very steep; almost vertical or perpendicular.

   "It was a sheer drop of 180 feet."