diff --git a/src/wp-admin/includes/class-custom-image-header.php b/src/wp-admin/includes/class-custom-image-header.php
index f8d1bb6630..c7ff42ab07 100644
--- a/src/wp-admin/includes/class-custom-image-header.php
+++ b/src/wp-admin/includes/class-custom-image-header.php
@@ -975,8 +975,8 @@ endif;
 		$file     = $file['file'];
 		$filename = wp_basename( $file );
 
-		// Construct the object array.
-		$object = array(
+		// Construct the array with attachment object data.
+		$attachment = array(
 			'post_title'     => $filename,
 			'post_content'   => $url,
 			'post_mime_type' => $type,
@@ -985,7 +985,7 @@ endif;
 		);
 
 		// Save the data.
-		$attachment_id = wp_insert_attachment( $object, $file );
+		$attachment_id = wp_insert_attachment( $attachment, $file );
 
 		return compact( 'attachment_id', 'file', 'filename', 'url', 'type' );
 	}
@@ -1061,14 +1061,14 @@ endif;
 		/** This filter is documented in wp-admin/includes/class-custom-image-header.php */
 		$cropped = apply_filters( 'wp_create_file_in_uploads', $cropped, $attachment_id ); // For replication.
 
-		$object = $this->create_attachment_object( $cropped, $attachment_id );
+		$attachment = $this->create_attachment_object( $cropped, $attachment_id );
 
 		if ( ! empty( $_POST['create-new-attachment'] ) ) {
-			unset( $object['ID'] );
+			unset( $attachment['ID'] );
 		}
 
 		// Update the attachment.
-		$attachment_id = $this->insert_attachment( $object, $cropped );
+		$attachment_id = $this->insert_attachment( $attachment, $cropped );
 
 		$url = wp_get_attachment_url( $attachment_id );
 		$this->set_header_image( compact( 'url', 'attachment_id', 'width', 'height' ) );
@@ -1300,7 +1300,7 @@ endif;
 	 *
 	 * @param string $cropped              Cropped image URL.
 	 * @param int    $parent_attachment_id Attachment ID of parent image.
-	 * @return array Attachment object.
+	 * @return array An array with attachment object data.
 	 */
 	final public function create_attachment_object( $cropped, $parent_attachment_id ) {
 		$parent     = get_post( $parent_attachment_id );
@@ -1310,7 +1310,7 @@ endif;
 		$size       = wp_getimagesize( $cropped );
 		$image_type = ( $size ) ? $size['mime'] : 'image/jpeg';
 
-		$object = array(
+		$attachment = array(
 			'ID'             => $parent_attachment_id,
 			'post_title'     => wp_basename( $cropped ),
 			'post_mime_type' => $image_type,
@@ -1319,7 +1319,7 @@ endif;
 			'post_parent'    => $parent_attachment_id,
 		);
 
-		return $object;
+		return $attachment;
 	}
 
 	/**
@@ -1327,15 +1327,15 @@ endif;
 	 *
 	 * @since 3.9.0
 	 *
-	 * @param array  $object  Attachment object.
-	 * @param string $cropped File path to cropped image.
+	 * @param array  $attachment An array with attachment object data.
+	 * @param string $cropped    File path to cropped image.
 	 * @return int Attachment ID.
 	 */
-	final public function insert_attachment( $object, $cropped ) {
-		$parent_id = isset( $object['post_parent'] ) ? $object['post_parent'] : null;
-		unset( $object['post_parent'] );
+	final public function insert_attachment( $attachment, $cropped ) {
+		$parent_id = isset( $attachment['post_parent'] ) ? $attachment['post_parent'] : null;
+		unset( $attachment['post_parent'] );
 
-		$attachment_id = wp_insert_attachment( $object, $cropped );
+		$attachment_id = wp_insert_attachment( $attachment, $cropped );
 		$metadata      = wp_generate_attachment_metadata( $attachment_id, $cropped );
 
 		// If this is a crop, save the original attachment ID as metadata.
@@ -1404,25 +1404,25 @@ endif;
 		/** This filter is documented in wp-admin/includes/class-custom-image-header.php */
 		$cropped = apply_filters( 'wp_create_file_in_uploads', $cropped, $attachment_id ); // For replication.
 
-		$object = $this->create_attachment_object( $cropped, $attachment_id );
+		$attachment = $this->create_attachment_object( $cropped, $attachment_id );
 
-		$previous = $this->get_previous_crop( $object );
+		$previous = $this->get_previous_crop( $attachment );
 
 		if ( $previous ) {
-			$object['ID'] = $previous;
+			$attachment['ID'] = $previous;
 		} else {
-			unset( $object['ID'] );
+			unset( $attachment['ID'] );
 		}
 
-		$new_attachment_id = $this->insert_attachment( $object, $cropped );
+		$new_attachment_id = $this->insert_attachment( $attachment, $cropped );
 
-		$object['attachment_id'] = $new_attachment_id;
-		$object['url']           = wp_get_attachment_url( $new_attachment_id );
+		$attachment['attachment_id'] = $new_attachment_id;
+		$attachment['url']           = wp_get_attachment_url( $new_attachment_id );
 
-		$object['width']  = $dimensions['dst_width'];
-		$object['height'] = $dimensions['dst_height'];
+		$attachment['width']  = $dimensions['dst_width'];
+		$attachment['height'] = $dimensions['dst_height'];
 
-		wp_send_json_success( $object );
+		wp_send_json_success( $attachment );
 	}
 
 	/**
@@ -1577,10 +1577,10 @@ endif;
 	 *
 	 * @since 4.9.0
 	 *
-	 * @param array $object A crop attachment object.
+	 * @param array $attachment An array with a cropped attachment object data.
 	 * @return int|false An attachment ID if one exists. False if none.
 	 */
-	public function get_previous_crop( $object ) {
+	public function get_previous_crop( $attachment ) {
 		$header_images = $this->get_uploaded_header_images();
 
 		// Bail early if there are no header images.
@@ -1591,7 +1591,7 @@ endif;
 		$previous = false;
 
 		foreach ( $header_images as $image ) {
-			if ( $image['attachment_parent'] === $object['post_parent'] ) {
+			if ( $image['attachment_parent'] === $attachment['post_parent'] ) {
 				$previous = $image['attachment_id'];
 				break;
 			}