Chordwise signifies to points in Sigil that are nearly opposite one another. This is as opposed to Radial, which means they're directly opposite.
Source: In the Cage: A Guide to Sigil, page 12
Earth? You actually named your world after dirt? Well, it has a sort of pithy quality to it I suppose...
— Planewalker plying the crosstrade in some obscure lemon
