primitive, original, earliest
+
- a part of the cell containing DNA and RNA and responsible for growth and reproduction
- the positively charged dense center of an atom
- a small group of indispensable persons or things
- (astronomy) the center of the head of a comet; consists of small solid particles of ice and frozen gas that vaporizes on approaching the sun to form the coma and tail
- any histologically identifiable mass of neural cell bodies in the brain or spinal cord
- the central structure of the lens that is surrounded by the cortex