diff --git a/Unix/t/01_opts.t b/Unix/t/01_opts.t
index 8405794..a79f203 100755
--- a/Unix/t/01_opts.t
+++ b/Unix/t/01_opts.t
@@ -125,6 +125,12 @@ my @Tests = (
                     'ref'  => '../tests/outputs/issues/166/fake.thy.yaml',
                 },
                 {
+                    'name' => '--read-lang-def w/triple_extension',
+                    'cd'   => '../tests/inputs',
+                    'args' => '--read-lang-def triple_lang_def.txt custom.triple.extension.js',
+                    'ref'  => '../tests/outputs/custom.triple.extension.js.yaml',
+                },
+                {
                     'name' => 'Forth balanced parentheses #1 (github issue #183)',
                     'cd'   => '../tests/inputs/issues/183',
                     'args' => 'file.fth',
diff --git a/cloc b/cloc
index f80f2d9..74bfb5a 100755
--- a/cloc
+++ b/cloc
@@ -4063,6 +4063,11 @@ sub classify_file {                          # {{{1
           $extension = lc $extension if $ON_WINDOWS;
           unshift @extension_list, $extension;  # examine double ext first
       }
+      if ($file =~ /\.([^\.]+\.[^\.]+\.[^\.]+)$/) { # has a triple extension
+          my $extension = $1;
+          $extension = lc $extension if $ON_WINDOWS;
+          unshift @extension_list, $extension;  # examine triple ext first
+      }
       foreach my $extension (@extension_list) {
         if ($Not_Code_Extension{$extension} and
            !$Forced_Extension{$extension}) {
diff --git a/tests/inputs/custom.triple.extension.js b/tests/inputs/custom.triple.extension.js
new file mode 100644
index 0000000..be707cd
--- /dev/null
+++ b/tests/inputs/custom.triple.extension.js
@@ -0,0 +1 @@
+js 4
diff --git a/tests/inputs/triple_lang_def.txt b/tests/inputs/triple_lang_def.txt
new file mode 100644
index 0000000..c87144d
--- /dev/null
+++ b/tests/inputs/triple_lang_def.txt
@@ -0,0 +1,6 @@
+Custom Triple JS
+    filter call_regexp_common C++
+    filter remove_inline //.*$
+    extension triple.extension.js
+    3rd_gen_scale 1.48
+    end_of_line_continuation \\$
diff --git a/tests/outputs/custom.triple.extension.js.yaml b/tests/outputs/custom.triple.extension.js.yaml
new file mode 100644
index 0000000..5889005
--- /dev/null
+++ b/tests/outputs/custom.triple.extension.js.yaml
@@ -0,0 +1,21 @@
+---
+# github.com/AlDanial/cloc
+header :
+  cloc_url           : github.com/AlDanial/cloc
+  cloc_version       : 1.67
+  elapsed_seconds    : 0.00475001335144043
+  n_files            : 1
+  n_lines            : 22
+  files_per_second   : 210.525724037545
+  lines_per_second   : 4631.56592882598
+  report_file        : glossary.json.yaml
+Custom Triple JS :
+  nFiles: 1
+  blank: 0
+  comment: 0
+  code: 1
+SUM:
+  blank: 0
+  comment: 0
+  code: 1
+  nFiles: 1