diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/filter/Combine.php b/core/modules/views/lib/Drupal/views/Plugin/views/filter/Combine.php
index cbb08b943f77..4a8b18ecd529 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/filter/Combine.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/filter/Combine.php
@@ -92,48 +92,48 @@ class Combine extends String {
   // By default things like op_equal uses add_where, that doesn't support
   // complex expressions, so override all operators.
 
-  function op_equal($field) {
+  function op_equal($expression) {
     $placeholder = $this->placeholder();
     $operator = $this->operator();
-    $this->query->add_where_expression($this->options['group'], "$field $operator $placeholder", array($placeholder => $this->value));
+    $this->query->add_where_expression($this->options['group'], "$expression $operator $placeholder", array($placeholder => $this->value));
   }
 
-  function op_contains($field) {
+  function op_contains($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field LIKE $placeholder", array($placeholder => '%' . db_like($this->value) . '%'));
+    $this->query->add_where_expression($this->options['group'], "$expression LIKE $placeholder", array($placeholder => '%' . db_like($this->value) . '%'));
   }
 
-  function op_starts($field) {
+  function op_starts($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field LIKE $placeholder", array($placeholder => db_like($this->value) . '%'));
+    $this->query->add_where_expression($this->options['group'], "$expression LIKE $placeholder", array($placeholder => db_like($this->value) . '%'));
   }
 
-  function op_not_starts($field) {
+  function op_not_starts($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field NOT LIKE $placeholder", array($placeholder => db_like($this->value) . '%'));
+    $this->query->add_where_expression($this->options['group'], "$expression NOT LIKE $placeholder", array($placeholder => db_like($this->value) . '%'));
   }
 
-  function op_ends($field) {
+  function op_ends($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field LIKE $placeholder", array($placeholder => '%' . db_like($this->value)));
+    $this->query->add_where_expression($this->options['group'], "$expression LIKE $placeholder", array($placeholder => '%' . db_like($this->value)));
   }
 
-  function op_not_ends($field) {
+  function op_not_ends($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field NOT LIKE $placeholder", array($placeholder => '%' . db_like($this->value)));
+    $this->query->add_where_expression($this->options['group'], "$expression NOT LIKE $placeholder", array($placeholder => '%' . db_like($this->value)));
   }
 
-  function op_not($field) {
+  function op_not($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field NOT LIKE $placeholder", array($placeholder => '%' . db_like($this->value) . '%'));
+    $this->query->add_where_expression($this->options['group'], "$expression NOT LIKE $placeholder", array($placeholder => '%' . db_like($this->value) . '%'));
   }
 
-  function op_regex($field) {
+  function op_regex($expression) {
     $placeholder = $this->placeholder();
-    $this->query->add_where_expression($this->options['group'], "$field RLIKE $placeholder", array($placeholder => $this->value));
+    $this->query->add_where_expression($this->options['group'], "$expression RLIKE $placeholder", array($placeholder => $this->value));
   }
 
-  function op_empty($field) {
+  function op_empty($expression) {
     if ($this->operator == 'empty') {
       $operator = "IS NULL";
     }
@@ -141,7 +141,7 @@ class Combine extends String {
       $operator = "IS NOT NULL";
     }
 
-    $this->query->add_where_expression($this->options['group'], "$field $operator");
+    $this->query->add_where_expression($this->options['group'], "$expression $operator");
   }
 
 }