In a linear manner. / In a straight line. / Sequentially in time; chronologically. / In the manner of a linear function. / (dance) Forward or backward, as opposed to laterally or diagonally.

(algebra, of a set of vectors or ring elements) Having a nontrivial linear combination which is zero.

(linear algebra) (Of a set of vectors or ring elements) whose nontrivial linear combinations are nonzero