Did You Know?
Today’s word has a straightforward line of descent. It comes from the Late Latin "rectilineus," which itself comes from the Latin words "rectus" ("straight") and "linea" ("line"). A lesser-known variant, "rectilineal," derives from the same Late Latin "rectilineus" and employs the "-al" suffix rather than "-ar." The grammarian H. W. Fowler dictated in 1926 that "there is no objection to either [variant] in itself, but '-ar' is so much commoner that, as there is no difference of meaning, '-al' should be abandoned as a needless variant." "Rectilineal" still turns up occasionally in spite of the redundancy, but "rectilinear" is by far the more common choice.
Quick Quiz: What 5-letter verb descends from "linea" and means "to bring into line"? The answer is ...