: into one side and out the other side of (something)
: from one side or end to another side or end of (something)
—used to describe movement within a place or an area of land, air, etc.
Full Definition of THROUGH
a (1) —used as a function word to indicate movement into at one side or point and out at another and especially the opposite side of <drove a nail through the board>(2): by way of <left through the door>(3) —used as a function word to indicate passage from one end or boundary to another <a highway through the forest><a road through the desert>(4): without stopping for :past<drove through a red light>
b —used as a function word to indicate passage into and out of a treatment, handling, or process <the matter has already passed through her hands>
—used as a function word to indicate means, agency, or intermediacy: as