Be consistent in the spelling of thread-safe(ty).
diff --git a/Doc/c-api/init.rst b/Doc/c-api/init.rst
index 1c62155..dbceecc 100644
--- a/Doc/c-api/init.rst
+++ b/Doc/c-api/init.rst
@@ -437,7 +437,7 @@
single: interpreter lock
single: lock, interpreter
-The Python interpreter is not fully thread safe. In order to support
+The Python interpreter is not fully thread-safe. In order to support
multi-threaded Python programs, there's a global lock, called the :dfn:`global
interpreter lock` or :dfn:`GIL`, that must be held by the current thread before
it can safely access Python objects. Without the lock, even the simplest