uppermost

Uppermost in his mind is the need for safety.

他当务之急是寻找一个安全的地方。

After hiking all day we finally reached the uppermost part of the mountain.

徒步走了一整天, 我们终于爬到了山顶。

During microdermabrasion, fine crystals usually remove the superficial or uppermost layer of the epidermis, known as the stratum corneum.

在微晶程中，微晶体能消除表上面的或者凸起的部位被称为角质层。