rec·ti·linear \“+\adjective Etymology: Late Latin rectilineus (from Latin rectus straight + linea line) + English -ar — more at right, line 1.: moving in a straight line : having an undeviating direction : forming a straight line 2. a.: characterized by straight lines b.: lying in a straight line : formed or bounded by straight lines 3.: perpendicular 5 • rec·ti·linearly\“+\adverb