WordPress at a glance
function is not described

WP_Query::get_queried_object() public WP 1.5.0

Retrieves the currently queried object.

If queried object is not set, then the queried object will be set from the category, tag, taxonomy, posts page, single post, page, or author query variable. After it is set up, it will be returned.

{} It's a method of the class: WP_Query{}

No Hooks.

Return

WP_Term/WP_Post_Type/WP_Post/WP_User/null. The queried object.

Usage

global $wp_query;
$wp_query->get_queried_object();

Changelog

Since 1.5.0 Introduced.

Code of WP_Query::get_queried_object() WP 5.6

<?php
public function get_queried_object() {
	if ( isset( $this->queried_object ) ) {
		return $this->queried_object;
	}

	$this->queried_object    = null;
	$this->queried_object_id = null;

	if ( $this->is_category || $this->is_tag || $this->is_tax ) {
		if ( $this->is_category ) {
			if ( $this->get( 'cat' ) ) {
				$term = get_term( $this->get( 'cat' ), 'category' );
			} elseif ( $this->get( 'category_name' ) ) {
				$term = get_term_by( 'slug', $this->get( 'category_name' ), 'category' );
			}
		} elseif ( $this->is_tag ) {
			if ( $this->get( 'tag_id' ) ) {
				$term = get_term( $this->get( 'tag_id' ), 'post_tag' );
			} elseif ( $this->get( 'tag' ) ) {
				$term = get_term_by( 'slug', $this->get( 'tag' ), 'post_tag' );
			}
		} else {
			// For other tax queries, grab the first term from the first clause.
			if ( ! empty( $this->tax_query->queried_terms ) ) {
				$queried_taxonomies = array_keys( $this->tax_query->queried_terms );
				$matched_taxonomy   = reset( $queried_taxonomies );
				$query              = $this->tax_query->queried_terms[ $matched_taxonomy ];

				if ( ! empty( $query['terms'] ) ) {
					if ( 'term_id' === $query['field'] ) {
						$term = get_term( reset( $query['terms'] ), $matched_taxonomy );
					} else {
						$term = get_term_by( $query['field'], reset( $query['terms'] ), $matched_taxonomy );
					}
				}
			}
		}

		if ( ! empty( $term ) && ! is_wp_error( $term ) ) {
			$this->queried_object    = $term;
			$this->queried_object_id = (int) $term->term_id;

			if ( $this->is_category && 'category' === $this->queried_object->taxonomy ) {
				_make_cat_compat( $this->queried_object );
			}
		}
	} elseif ( $this->is_post_type_archive ) {
		$post_type = $this->get( 'post_type' );
		if ( is_array( $post_type ) ) {
			$post_type = reset( $post_type );
		}
		$this->queried_object = get_post_type_object( $post_type );
	} elseif ( $this->is_posts_page ) {
		$page_for_posts          = get_option( 'page_for_posts' );
		$this->queried_object    = get_post( $page_for_posts );
		$this->queried_object_id = (int) $this->queried_object->ID;
	} elseif ( $this->is_singular && ! empty( $this->post ) ) {
		$this->queried_object    = $this->post;
		$this->queried_object_id = (int) $this->post->ID;
	} elseif ( $this->is_author ) {
		$this->queried_object_id = (int) $this->get( 'author' );
		$this->queried_object    = get_userdata( $this->queried_object_id );
	}

	return $this->queried_object;
}