diff --git a/src/txorphanage.h b/src/txorphanage.h
--- a/src/txorphanage.h
+++ b/src/txorphanage.h
@@ -13,7 +13,12 @@
 /** Guards orphan transactions and extra txs for compact blocks */
 extern RecursiveMutex g_cs_orphans;
 
-/** Data structure to keep track of orphan transactions */
+/**
+ * A class to track orphan transactions (failed on TX_MISSING_INPUTS)
+ * Since we cannot distinguish orphans from bad transactions with
+ * non-existent inputs, we heavily limit the number of orphans
+ * we keep and the duration we keep them for.
+ */
 class TxOrphanage {
 public:
     /** Add a new orphan transaction */
@@ -24,7 +29,8 @@
     bool HaveTx(const TxId &txid) const LOCKS_EXCLUDED(g_cs_orphans);
 
     /**
-     * Get the details of an orphan transaction (returns nullptr if not found)
+     * Get an orphan transaction and its originating peer
+     * (Transaction ref will be nullptr if not found)
      */
     std::pair<CTransactionRef, NodeId> GetTx(const TxId &txid) const
         EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans);
@@ -37,7 +43,7 @@
      */
     void EraseForPeer(NodeId peer) EXCLUSIVE_LOCKS_REQUIRED(g_cs_orphans);
 
-    /** Erase all orphans included in / invalidated by a new block */
+    /** Erase all orphans included in or invalidated by a new block */
     void EraseForBlock(const CBlock &block) LOCKS_EXCLUDED(g_cs_orphans);
 
     /** Limit the orphanage to the given maximum */