diff --git a/testing/mochitest/runtests.py b/testing/mochitest/runtests.py
index 431409bb2b02..2c8b319b4cc8 100644
--- a/testing/mochitest/runtests.py
+++ b/testing/mochitest/runtests.py
@@ -1061,7 +1061,7 @@ class Mochitest(MochitestUtilsMixin):
       self.cleanup(manifest, options)
     return status
 
-  def handleTimeout(self, timeout, proc, utilityPath, debuggerInfo, browserProcesssId):
+  def handleTimeout(self, timeout, proc, utilityPath, debuggerInfo, browserProcessId):
     """handle process output timeout"""
     # TODO: bug 913975 : _processOutput should call self.processOutputLine one more time one timeout (I think)
     log.info("TEST-UNEXPECTED-FAIL | %s | application timed out after %d seconds with no output", self.lastTestSeen, int(timeout))