diff --git a/lib/runnable.js b/lib/runnable.js
index 1045b0680b..7c26f56970 100644
--- a/lib/runnable.js
+++ b/lib/runnable.js
@@ -103,7 +103,7 @@ Runnable.prototype.slow = function (ms) {
   if (typeof ms === 'string') {
     ms = milliseconds(ms);
   }
-  debug('timeout %d', ms);
+  debug('slow %d', ms);
   this._slow = ms;
   return this;
 };