minulostí
Minulostí is the instrumental singular form of the Czech noun minulost, which means "the past" or "past events." Grammatically, minulost is a feminine noun, and its instrumental singular form is minulostí. Other singular forms include nominative minulost, genitive minulosti, dative minulosti, accusative minulost, and locative minulosti (the same form as genitive and dative). The term is used in linguistic discussion as well as in literary or formal language to refer to the past as a temporal context.
Etymology and meaning: Minulost derives from the adjective minulý, meaning "past." It is related to Proto-Slavic
Usage: In everyday Czech, people more often refer to the past with the prepositional phrase "v minulosti"