diff --git a/CHANGES/4986.doc b/CHANGES/4986.doc
new file mode 100644
index 00000000000..94329dcb063
--- /dev/null
+++ b/CHANGES/4986.doc
@@ -0,0 +1 @@
+Spelling: Change canonize to canonicalize.
diff --git a/docs/client_quickstart.rst b/docs/client_quickstart.rst
index d349b8c5c5e..a6e7c940b22 100644
--- a/docs/client_quickstart.rst
+++ b/docs/client_quickstart.rst
@@ -115,18 +115,18 @@ is not encoded by library. Note that ``+`` is not encoded::
 
 .. note::
 
-   *aiohttp* internally performs URL canonization before sending request.
+   *aiohttp* internally performs URL canonicalization before sending request.
 
-   Canonization encodes *host* part by :term:`IDNA` codec and applies
+   Canonicalization encodes *host* part by :term:`IDNA` codec and applies
    :term:`requoting` to *path* and *query* parts.
 
    For example ``URL('http://example.com/путь/%30?a=%31')`` is converted to
    ``URL('http://example.com/%D0%BF%D1%83%D1%82%D1%8C/0?a=1')``.
 
-   Sometimes canonization is not desirable if server accepts exact
+   Sometimes canonicalization is not desirable if server accepts exact
    representation and does not requote URL itself.
 
-   To disable canonization use ``encoded=True`` parameter for URL construction::
+   To disable canonicalization use ``encoded=True`` parameter for URL construction::
 
       await session.get(
           URL('http://example.com/%30', encoded=True))