10 letters · 16 points in Scrabble
noun any of a group of very small rod-shaped bacteria that live in biting arthropods (as ticks and mites) and cause disease in vertebrate hosts; they cause typhus and other febrile diseases in human beings
originBorrowed from translingual Rickettsia (genus name), from Howard Taylor Ricketts, equivalent to Ricketts + -ia.
Etymology from Wiktionary, CC BY-SA 3.0