be a rare occurrence
1rare occurrence — index improbability, phenomenon (unusual occurrence) Burton s Legal Thesaurus. William C. Burton. 2006 …
2occurrence — oc|cur|rence [əˈkʌrəns US əˈkə: ] n 1.) something that happens →↑occurrence frequent/rare/common occurrence ▪ Laughter was a rare occurrence in his classroom. ▪ Flooding in the area is a common occurrence. 2.) [singular] the fact of something… …
3occurrence — noun 1 (C) something that happens: a common/rare/regular occurrence:: Flooding under this bridge is a common occurrence. | Laughter was a rare occurrence in his classroom. 2 (U) the fact of something happening: the frequent occurrence of violent… …
4occurrence — noun 1) vandalism used to be a rare occurrence Syn: event, incident, happening, phenomenon, affair, matter, circumstance 2) the occurrence of cancer increases with age Syn: existence, instance, appearance, manifesta …
5occurrence — noun 1) a rare occurrence Syn: event, incident, happening, phenomenon, circumstance 2) the occurrence of cancer Syn: existence, instance, appearance, frequency, incidence, rate …
6occurrence — [ ɔkyrɑ̃s ] n. f. • 1440; du lat. occurrere → occurrent 1 ♦ Littér. Cas, circonstance. « changeant de route suivant l occurrence » ( Balzac). Mod. (dans des loc.) EN L OCCURRENCE : dans le cas présent. La personne responsable, en l occurrence, M …
7Rare earth element — Rare earth ore, shown with a United States penny for size comparison These rare …
8occurrence — noun ADJECTIVE ▪ common, everyday, widespread ▪ daily, frequent, regular ▪ rare, uncommon ▪ …
9rare-earth element — /rair errth /, Chem. any of a group of closely related metallic elements, comprising the lanthanides, scandium, and yttrium, that are chemically similar by virtue of having the same number of valence electrons. Also called rare earth metal. [1955 …
10Rare Earth hypothesis — In planetary astronomy and astrobiology, the Rare Earth hypothesis argues that the emergence of complex multicellular life (metazoa) on Earth required an improbable combination of astrophysical and geological events and circumstances. The term… …
