tract
名词 tract:
an extended area of land
同义词:piece of land, piece of ground, parcel of land, parcel
a system of body parts that together serve some particular purpose
a brief treatise on a subject of interest; published in the form of a booklet
同义词:pamphlet
a bundle of myelinated nerve fibers following a path through the brain
同义词:nerve pathway, nerve tract, pathway