functions.php

<?php

function orbis_timesheets_init() {
	// @see http://codex.wordpress.org/Function_Reference/register_taxonomy
	register_taxonomy(
		'orbis_timesheets_activity', // taxonomy name
		null, // object type
		array( // arguments
			'hierarchical'      => true,
			'labels'            => array(
				'name'              => _x( 'Timesheets Activities', 'taxonomy general name', 'orbis_timesheets' ),
				'singular_name'     => _x( 'Timesheets Activity', 'taxonomy singular name', 'orbis_timesheets' ),
				'search_items'      => __( 'Search Timesheets Activities', 'orbis_timesheets' ),
				'all_items'         => __( 'All Timesheets Activities', 'orbis_timesheets' ),
				'parent_item'       => __( 'Parent Timesheets Activity', 'orbis_timesheets' ),
				'parent_item_colon' => __( 'Parent Activity:', 'orbis_timesheets' ),
				'edit_item'         => __( 'Edit Activity', 'orbis_timesheets' ),
				'update_item'       => __( 'Update Activity', 'orbis_timesheets' ),
				'add_new_item'      => __( 'Add New Activity', 'orbis_timesheets' ),
				'new_item_name'     => __( 'New Activity Name', 'orbis_timesheets' ),
				'menu_name'         => __( 'Activities', 'orbis_timesheets' ),
			),
			'show_ui'           => true,
			'show_admin_column' => true,
			'query_var'         => true,
			'rewrite'           => array( 'slug' => 'genre' ),
		)
	);
}

add_action( 'init', 'orbis_timesheets_init' );