Betacoronavirus the Latin “corona” meaning crown or halo, referring to their image under electron microscopy of crown-like spikes on their surface similar to the solar corona. This morphology is created by the viral spike (S) peplomers, which are proteins that populate the surface of the virus and determine host tropism. The order Nidovirales is named for the Latin nidus, which means nest. It refers to this order’s production of a 3' co-terminal nested set of subgenomic mRNA's during infection. Betacoronavirus Betacoronaviruses are one of four genera of coronaviruses of the subfamily "Coronavirinae" in the family "Coronaviridae", of the order "Nidovirales". They
Eureka (word) Fermat polygonal number theorem. Eureka (word) Eureka () is an interjection used to celebrate a discovery or invention. It is a transliteration of an exclamation attributed to Ancient Greek mathematician and inventor Archimedes. "Eureka" comes from the Ancient Greek word "heúrēka", meaning "I found (it)", which is the first person singular perfect indicative active of the verb "heuriskō" "I find". It is closely related to heuristic, which refers to experience-based techniques for problem solving, learning, and discovery. The accent of the English word is on the second syllable, following Latin rules of accent, which require that a penult (next-to-last syllable)