The term 'arranged in a line' can be described by four different words: ECHELON (7 letters), tabular (7 letters), NEAT (4 letters) and seriate (7 letters). ECHELON is a military formation in which troops are arranged in a line with each successive rank slightly offset from the one in front. Tabular refers to something that is arranged in a table or chart form. NEAT means orderly and tidy. Seriate is an arrangement of items in a series or sequence.