gnetopsida: gymnospermous flowering plants; supposed link between conifers and angiosperms; in some systems classified as a class (Gnetopsida) and in others as a subdivision (Gnetophytina or Gnetophyta)
gordian knot: an intricate knot tied by Gordius, the king of Phrygia, and cut by the sword of Alexander the Great after he heard that whoever undid it would become ruler of Asia