Eruptivity

Part of speech: noun

Definitions

1. The attribute of having a tendency to produce sudden and forceful eruptions or explosions related to geological processes
2. The quality of being prone to sudden and intense outbursts or explosions, especially in geological contexts
3. A characteristic that denotes likelihood of forceful volcanic activity or explosive release

Etymology: "Eruptivity" is a plain formation: the adjective "eruptive" with the suffix "-ity," which turns an adjective into a noun meaning "the quality of being." The suffix comes from Latin "-itas" through Old French "-ite," and it has been attached to English adjectives for centuries, so the noun simply names the property the adjective describes. The adjective "eruptive" is the more interesting half. It comes from the Latin verb "erumpere," meaning "to break out" or "burst forth," built from "e-" (out) and "rumpere" (to break). That same root gives English "rupture" and "abrupt," so eruptivity is, at bottom, a word about something bursting out of a closed space. In geology, "eruptive" was applied to rocks formed from molten material that has broken through to the surface, which is why the term is still tied to volcanic and igneous contexts. The noun extends that sense from the event itself to the tendency to erupt, so a volcano or a magma body with high eruptivity is one prone to violent outbursts.

Synonyms: explosiveness, volcanicity, outburst