What is the meaning of Být?

to be

to be (to exist)

used to form past tense forms of verbs with past participles

used to form future tense forms of verbs with infinitives

used to form conditional mood forms of verbs with past participles

used to form passive voice forms of verbs with passive participles

used to form conditional forms of verbs with past and passive participles

Source: wiktionary.org