The name is also used to describe other edible seeds from the Fabaceae like the pigeon pea (Cajanus cajan), the cowpea (Vigna unguiculata) and the seeds from several species of Lathyrus.
That's a strange coincidence. Just the other day, my wife asked me what I wanted for dinner, and I said I wanted to eat her Vigna unguiculata, and she slapped me......