diff --git a/CHANGES.md b/CHANGES.md
index 59324b44b6..5ca677923e 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,6 +2,7 @@
 
 Grammars:
 
+- fix(python) def, class keywords detected mid-identifier (#3381) [Josh Goebel][]
 - fix(python) Fix recognition of numeric literals followed by keywords without whitespace (#2985) [Richard Gibson][]
 - enh(swift) add SE-0290 unavailability condition (#3382) [Bradley Mackey][]
 - enh(java) add `sealed` and `non-sealed` keywords (#3386) [Bradley Mackey][]
@@ -22,6 +23,7 @@ Developer Tools:
 [Richard Gibson]: https://github.com/gibson042
 [Bradley Mackey]: https://github.com/bradleymackey
 [Björn Ebbinghaus]: https://github.com/MrEbbinghaus
+[Josh Goebel]: https://github.com/joshgoebel
 
 ## Version 11.3.1
 
diff --git a/src/languages/python.js b/src/languages/python.js
index 46ed88a6f0..cb152d1b6c 100644
--- a/src/languages/python.js
+++ b/src/languages/python.js
@@ -384,7 +384,7 @@ export default function(hljs) {
       hljs.HASH_COMMENT_MODE,
       {
         match: [
-          /def/, /\s+/,
+          /\bdef/, /\s+/,
           IDENT_RE,
         ],
         scope: {
@@ -397,14 +397,14 @@ export default function(hljs) {
         variants: [
           {
             match: [
-              /class/, /\s+/,
+              /\bclass/, /\s+/,
               IDENT_RE, /\s*/,
               /\(\s*/, IDENT_RE,/\s*\)/
             ],
           },
           {
             match: [
-              /class/, /\s+/,
+              /\bclass/, /\s+/,
               IDENT_RE
             ],
           }
diff --git a/test/markup/python/false_positives.expect.txt b/test/markup/python/false_positives.expect.txt
new file mode 100644
index 0000000000..cce88e6df8
--- /dev/null
+++ b/test/markup/python/false_positives.expect.txt
@@ -0,0 +1,5 @@
+foo = _undef
+bar
+
+booger = _unclass
+burger
diff --git a/test/markup/python/false_positives.txt b/test/markup/python/false_positives.txt
new file mode 100644
index 0000000000..cce88e6df8
--- /dev/null
+++ b/test/markup/python/false_positives.txt
@@ -0,0 +1,5 @@
+foo = _undef
+bar
+
+booger = _unclass
+burger