1. Root

 ǵʰreh₁i̯, ǵʰrei̯h₁

2. Lexical meanings

 EN: rub

3. Comparative evidence

4. Formally comparable roots

 1.ǵʰer, 2.ǵʰer, 3.ǵʰer, 4.ǵʰer, ǵʰerh₁, ǵʰerh₂, ǵʰerh₃, ǵʰers, ǵʰreh₁d, ǵʰrei̯h₁, ǵʰrei̯h₂, ǵʰrei̯h₃, ǵʰrei̯h₁s

5. Formally/Semantically comparable roots

 ǵʰrei̯h₁s

6. Revised root variants

7. Comments

8. References

Watkins 2011 = Watkins, Calvert. 2011. The American heritage dictionary of Indo-European roots. 3rd revised ed. Boston, New York: Houghton Mifflin Harcourt.