A root probably identical with that of niyr, through the idea of the gleam of a fresh furrow; to till the soil -- break up.
see HEBREW niyr
H5214. nir
I. [נִיר] verb break up, freshly till; —
Qal Imperative masculine plural נִ֫ירוּ, with accusative of congnate meaning with verb נִיר Hosea 10:12; Jeremiah 4:3.