Throughout the world, ธีรฤทธิ์ (Theerit 
, ธีรฤทธิ์ , Theenarit ) is a very rare principally masculine, but very infrequently girly first name. The forename ธีรฤทธิ์ is habitual in South-eastern Asia, particularly Thailand, where it is a very rare predominantly boy's, but very infrequently feminine name.
ก. ศรีสุวรรณ, ไวโรจนกิจ, ธนอุดมนาน, and ฤทธิมัต