1
capitalized : a genus of sporozoan protozoans (family Theileriidae) that includes a parasite (T. parva) causing east coast fever of cattle
2
plural theileriae -ē-ˌē How to pronounce theileria (audio) also theilerias : any organism of the genus Theileria

Browse Nearby Words

Cite this Entry

“Theileria.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/theileria. Accessed 8 Jul. 2026.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!