diff --git a/src/coins.h b/src/coins.h
--- a/src/coins.h
+++ b/src/coins.h
@@ -280,11 +280,10 @@
     const Coin &AccessCoin(const COutPoint &output) const;
 
     /**
-     * Add a coin. Set potential_overwrite to true if an unspent version may
+     * Add a coin. Set possible_overwrite to true if an unspent version may
      * already exist in the cache.
      */
-    void AddCoin(const COutPoint &outpoint, Coin coin,
-                 bool potential_overwrite);
+    void AddCoin(const COutPoint &outpoint, Coin coin, bool possible_overwrite);
 
     /**
      * Spend a coin. Pass moveto in order to get the deleted data.
diff --git a/src/coins.cpp b/src/coins.cpp
--- a/src/coins.cpp
+++ b/src/coins.cpp
@@ -142,13 +142,14 @@
 }
 
 void AddCoins(CCoinsViewCache &cache, const CTransaction &tx, int nHeight,
-              bool check) {
+              bool check_for_overwrite) {
     bool fCoinbase = tx.IsCoinBase();
     const TxId txid = tx.GetId();
     for (size_t i = 0; i < tx.vout.size(); ++i) {
         const COutPoint outpoint(txid, i);
-        bool overwrite = check ? cache.HaveCoin(outpoint) : fCoinbase;
-        // Always set the possible_overwrite flag to AddCoin for coinbase txn,
+        bool overwrite =
+            check_for_overwrite ? cache.HaveCoin(outpoint) : fCoinbase;
+        // Coinbase transactions can always be overwritten,
         // in order to correctly deal with the pre-BIP30 occurrences of
         // duplicate coinbase transactions.
         cache.AddCoin(outpoint, Coin(tx.vout[i], nHeight, fCoinbase),
diff --git a/src/test/coins_tests.cpp b/src/test/coins_tests.cpp
--- a/src/test/coins_tests.cpp
+++ b/src/test/coins_tests.cpp
@@ -813,10 +813,10 @@
     /**
      * Check AddCoin behavior, requesting a new coin from a cache view, writing
      * a modification to the coin, and then checking the resulting entry in the
-     * cache after the modification. Verify behavior with the with the AddCoin
-     * potential_overwrite argument set to false, and to true.
+     * cache after the modification. Verify behavior with the AddCoin
+     * possible_overwrite argument set to false, and to true.
      *
-     * Cache   Write   Result  Cache        Result       potential_overwrite
+     * Cache   Write   Result  Cache        Result       possible_overwrite
      * Value   Value   Value   Flags        Flags
      */
     CheckAddCoin(ABSENT, VALUE3, VALUE3, NO_ENTRY, DIRTY | FRESH, false);
diff --git a/src/validation.cpp b/src/validation.cpp
--- a/src/validation.cpp
+++ b/src/validation.cpp
@@ -1349,10 +1349,11 @@
                                         alternate.IsCoinBase());
     }
 
-    // The potential_overwrite parameter to AddCoin is only allowed to be false
-    // if we know for sure that the coin did not already exist in the cache. As
-    // we have queried for that above using HaveCoin, we don't need to guess.
-    // When fClean is false, a coin already existed and it is an overwrite.
+    // If the coin already exists as an unspent coin in the cache, then the
+    // possible_overwrite parameter to AddCoin must be set to true. We have
+    // already checked whether an unspent coin exists above using HaveCoin, so
+    // we don't need to guess. When fClean is false, an unspent coin already
+    // existed and it is an overwrite.
     view.AddCoin(out, std::move(undo), !fClean);
 
     return fClean ? DisconnectResult::OK : DisconnectResult::UNCLEAN;