Looking up...
to exist or to have a particular identity, state, or condition
Il est médecin.
He is a doctor.
Nous sommes prêts.
We are ready.
Used as an auxiliary verb for many compound tenses (e.g., passé composé).
Remember that 'être' is the auxiliary for most intransitive verbs in the passé composé, while 'avoir' is used for transitive verbs.
From Latin 'esse', meaning 'to be'. The modern form evolved through Old French 'estre'.
Irregular verb; used as auxiliary for most verbs in the passé composé. The past participle agrees with the subject when used as a main verb (e.g., 'elle est partie').