Typo in last docstring.

1 files changed, 1 insertions, 1 deletions

diff --git a/coverage/control.py b/coverage/control.py
index 2ca43447..d03c69b3 100644
--- a/coverage/control.py
+++ b/coverage/control.py
@@ -78,7 +78,7 @@ class coverage:
     def exclude(self, regex):
         """Exclude source lines from execution consideration.
         
-        `regex` is a regular expression.  Lines matching this expressions are
+        `regex` is a regular expression.  Lines matching this expression are
         not considered executable when reporting code coverage.  A list of
         regexes is maintained; this function adds a new regex to the list.
         Matching any of the regexes excludes a source line.