[krip-tuh-zoh-ik] 
| 1. | (initial capital letter ) Geology. of or pertaining to that part of Precambrian time whose stratigraphic record yields only sparse, primitive fossils. |
| 2. | Zoology. living in concealed or secluded places. |
| 3. | (initial capital letter) Geology. the part of Precambrian time whose stratigraphic record yields only sparse, primitive fossils. |