|ammonoid (ām'ə-noid') Pronunciation Key
Any of various extinct cephalopods of the subclass Ammonoidea living from the Devonian to the Cretaceous Periods. Ammonoids had a symmetrical, coiled, chambered shell with angular sutures between the chambers. They are closely related to the nautiloids, including the modern-day chambered nautilus.
|a children's mummer's parade, as on the Fourth of July, with prizes for the best costumes.|
|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|