*Thierry (m) - ''see Derek'' ('''Saint''')
*Thomas (m) - [[Apostle Thomas]] ('''Saint''')
*Thor (m) - St Thorgyth the Ascetic ([[January 25]] - '''Sound-alike''') [http://christopherklitou.com/when_is_my_nameday_t.htm]
*Tia (f) - St [[Tatiana of Rome]] ('''Sound-alike'''); or, saints ending in '-tia' ('''Sound-alike'''); or, St Thais ([[May 10]] - '''Sound-alike''').
*Tiana (f) - ''see Tatiana or Christiana'' ('''Diminutive''')