baixest

Etymology
Probably from with the ending  by analogy with. Alternatively, from earlier (from ), by a chain of association: "leap year" > "year of misfortune" > "depression in the landscape", with a change in spelling due to association with. In the latter case, a doublet of.

Noun

 * 1)  slope, declivity
 * 2)  depression, especially one enclosed by higher terrain; coombe