“Nisus” comes from the Latin words “nīsus” (“effort”) and “nītī” (“to strive”). It’s mostly used in a philosophical sense to refer to the concerted, dedicated effort required for a specific goal. It was used widely by 18th- and 19th-century thinkers to describe processes of governmental, scientific, and personal development. For example, 19th-century German biologist and philosopher Hans Driesch used the term as such: “The universe has a forward thrust, called its ‘nisus’ (broadly to be identified with the Time aspect) in virtue of which further levels are to be expected.”