noun: A Roman cognomen, notably borne by Publius (or Gaius) Cornelius Tacitus (c.56-117), a historian of ancient Rome and Marcus Claudius Tacitus (c.200-275), a Roman emperor.
noun: A lunar impact crater.
noun: (medicine) Acronym of Thyroid Allostasis in Critical Illness, Tumours, Uraemia and Starvation.
