undifferentiated

Short definition from Wiktionary

Adjective

1. 1
   Not differentiated, not different, alike.
2. 2
   Not differentiated, not different, alike: Describing tissues where the individual cells have not yet developed mature or distinguishing features, or describes embryonic organisms where the organs cannot be identified.
3. 3
   Not differentiated, not different, alike: Describing a plant body where the vascular tissue has not developed, as in the thallophytes.