1. Root

 ker, kar

2. Lexical meanings

 EN: hard

3. Comparative evidence

4. Formally comparable roots

 1.kerh₁, 1.kerh₂, 1.kerh₃, 1.kert, 1.kreu̯h₁, 1.kreu̯h₂, 1.kreu̯h₃, 1.ker, 1.kers, 2.kerh₁, 2.kerh₂, 2.kerh₃, 2.kers, 2.kreu̯h₂, 2.kert, 2.ker, 3.kerh₁, 3.kerh₂, 3.kerh₃, krei̯h₁, krei̯h₂, krei̯h₃, kreph₁, kreph₂, kreph₃, kar, kars, kreh₁, kreh₁i̯, kreh₂, kret, kreu̯s, kreḱ, kremh₁, kremh₂, kremh₃, krend, kreph₁, kreph₂, kreph₃, kerd, kerḱ, krei̯p, kerb, kerbʰ, kerh₁, kerh₂, kerh₃, kerp, kers, kert, kreb, krengʷ, krei̯, kremh₁, kremh₂, kremh₃

5. Formally/Semantically comparable roots

6. Revised root variants

7. Comments

8. References