Quick answer
Agamemnon is a boy name meaning "very steadfast".
Pronunciation: Classical Greek /a.ɡa.mém.nɔːn/; American English /æɡ.ə.ˈmɛm.nɑn/; British English /æɡ.ə.ˈmɛm.nɒn/.
Meaning and history
Possibly means "very steadfast" in Greek, from ἄγαν ( agan ) "very much" and μένω ( meno ) "to stay". In Greek mythology he was the brother of Menelaus. He led the Greek expedition to Troy to recover his brother's wife Helen. After the Trojan War Agamemnon was killed by his wife Clytemnestra.
Notes and context
Usage: greek mythology, greek | Ancient Greek: Ἀγαμέμνων; Greek: Αγαμέμνων