WordPress at a glance
filter is not described

the_excerpt filter-hook . WP 0.71

Filters the displayed post excerpt.

Usage

add_filter( 'the_excerpt', 'filter_function_name_302' );
function filter_function_name_302( $post_excerpt ){
	// filter...

	return $post_excerpt;
}
$post_excerpt(string)
The post excerpt.

Where the hook is called

the_excerpt()
WP_REST_Attachments_Controller::prepare_item_for_response()
WP_REST_Revisions_Controller::prepare_excerpt_response()
WP_REST_Posts_Controller::prepare_item_for_response()
do_trackbacks()
wp-includes/post-template.php 362
echo apply_filters( 'the_excerpt', get_the_excerpt() );
wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php 317
$caption         = apply_filters( 'the_excerpt', apply_filters( 'get_the_excerpt', $post->post_excerpt, $post ) );
wp-includes/rest-api/endpoints/class-wp-rest-revisions-controller.php 749
$excerpt = apply_filters( 'the_excerpt', $excerpt, $post );
wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php 1528
$excerpt = apply_filters( 'the_excerpt', apply_filters( 'get_the_excerpt', $post->post_excerpt, $post ) );
wp-includes/comment.php 2536
$excerpt = apply_filters( 'the_excerpt', $post->post_excerpt );

Where the hook is used (in WP core)

wp-includes/default-filters.php 167
add_filter( 'the_excerpt', 'wptexturize' );
wp-includes/default-filters.php 168
add_filter( 'the_excerpt', 'convert_smilies' );
wp-includes/default-filters.php 169
add_filter( 'the_excerpt', 'convert_chars' );
wp-includes/default-filters.php 170
add_filter( 'the_excerpt', 'wpautop' );
wp-includes/default-filters.php 171
add_filter( 'the_excerpt', 'shortcode_unautop');