di·a·ste·ma \ˌdīəˈstēmə\noun (pluraldi·a·ste·ma·ta \-tēməd.ə, -tem-\) Etymology: New Latin, from Late Latin, interval 1.: the modified cytoplasm in the equatorial plane during mitosis that indicates the division plane of the cell 2.: a space between teeth in a jaw • di·a·ste·mat·ic\|dīəstə|mad.ik\adjective