Merriam-Webster's Collegiate® Dictionary, 11th Edition
FALLOW
I. adjective
Etymology: Middle English falow, from Old English fealu; akin to Old High German falo pale, fallow, Latin pallēre to be pale, Greek polios gray Date: before 12th century of a light yellowish-brown color,
II. noun see: felly Date: before 12th century usually cultivated land that is allowed to lie idle during the growing season, plowed land, the state or period of being fallow, the tilling of land without sowing it for a season,
III. transitive verb
Date: 15th century
to plow, harrow, and break up (land) without seeding to destroy weeds and conserve soil moisture,
IV. adjective
Date: 15th century
left untilled or unsown after plowing, dormant , inactive , fallowness noun