trituberculy

noun

1. A theory of the development of mammalian molar teeth. The primitive stage is that of simple cones, as in reptiles. The simple cone then developed a smaller cone in front and another behind. Next, a <i>cingulum</i> was developed, and the three cones became arranged in a triangle, the two smaller cusps having moved to the outer side in upper and to the inner in lower molars. This primitive triangle is called the <i>trigon</i> or <i>trigonid</i> and this stage the <i>tritubercular</i> or <i>trigonodont</i>. The trigon being a cutting apparatus, an extension of the posterior part of the crown was developed in lower molars for crushing, and a smaller corresponding part appeared in upper molars. Another large cone then arose, usually from the cingulum. In more complex forms, smaller intermediate cusps appeared.

   noun

   Source: webster1913