diff --git a/src/processor/mine.rs b/src/processor/mine.rs
index e941040..efc036f 100644
--- a/src/processor/mine.rs
+++ b/src/processor/mine.rs
@@ -79,7 +79,7 @@ pub fn process_mine<'a, 'info>(
 
     // Calculate the hash from the provided nonce
     let noise_data = noise_info.data.borrow();
-    let hx = drillx::hash(&proof.hash, &args.nonce, &noise_data);
+    let hx = drillx::hash(&proof.challenge, &args.nonce, &noise_data);
     drop(noise_data);
 
     // Validate hash satisfies the minimnum difficulty
@@ -139,7 +139,7 @@ pub fn process_mine<'a, 'info>(
     proof.balance = proof.balance.saturating_add(reward);
 
     // Hash recent slot hash into the next challenge to prevent pre-mining attacks
-    proof.hash = hashv(&[
+    proof.challenge = hashv(&[
         hx.as_slice(),
         &slot_hashes_info.data.borrow()[0..size_of::<SlotHash>()],
     ])
diff --git a/src/processor/register.rs b/src/processor/register.rs
index acaf52d..4ad7c15 100644
--- a/src/processor/register.rs
+++ b/src/processor/register.rs
@@ -59,7 +59,7 @@ pub fn process_register<'a, 'info>(
     let proof = Proof::try_from_bytes_mut(&mut proof_data)?;
     proof.authority = *signer.key;
     proof.balance = 0;
-    proof.hash = hashv(&[
+    proof.challenge = hashv(&[
         signer.key.as_ref(),
         &slot_hashes_info.data.borrow()[0..size_of::<SlotHash>()],
     ])
diff --git a/src/state/proof.rs b/src/state/proof.rs
index 24ea148..e2913d1 100644
--- a/src/state/proof.rs
+++ b/src/state/proof.rs
@@ -18,8 +18,8 @@ pub struct Proof {
     /// The quantity of tokens this miner has staked or earned.
     pub balance: u64,
 
-    /// The proof's current hash.
-    pub hash: [u8; 32],
+    /// The current mining challenge.
+    pub challenge: [u8; 32],
 
     /// The last slot ore was deposited into this account.
     pub last_deposit_slot: u64,