The term name to add, or a WP_Error object if there’s an error.
$taxonomystring
Taxonomy slug.
$argsarray|string
Array or query string of arguments passed to wp_insert_term() .More Arguments from wp_insert_term( … $args )Array or query string of arguments for inserting a term.
alias_ofstring
Slug of the term to make this term an alias of. Default empty string. Accepts a term slug.