diff --git a/ch10_network.adoc b/ch10_network.adoc
index d2a78282..3d4fd583 100644
--- a/ch10_network.adoc
+++ b/ch10_network.adoc
@@ -1170,7 +1170,7 @@ online tutorials.
 [[mempool]]
 === Mempools and Orphan Pools
 
-Almost every node on the Bitcoin
+Almost((("Bitcoin network", "mempools")))((("Bitcoin network", "orphan pools")))((("memory pool")))((("orphan pools")))((("unconfirmed transactions")))((("transactions", "unconfirmed"))) every node on the Bitcoin
 network maintains a temporary list of unconfirmed transactions called
 the _memory pool_ (_mempool_). Nodes use this pool
 to keep track of transactions that are known to the network but are not