diff --git a/halo2_proofs/src/plonk/lookup/verifier.rs b/halo2_proofs/src/plonk/lookup/verifier.rs
index 52b00d04..db4394f2 100644
--- a/halo2_proofs/src/plonk/lookup/verifier.rs
+++ b/halo2_proofs/src/plonk/lookup/verifier.rs
@@ -140,7 +140,7 @@ impl<C: CurveAffine> Evaluated<C> {
 
         std::iter::empty()
             .chain(
-                // l_0(X) * (1 - z'(X)) = 0
+                // l_0(X) * (1 - z(X)) = 0
                 Some(l_0 * &(C::Scalar::one() - &self.product_eval)),
             )
             .chain(