Celtic Meaning: The name Eoin is a Celtic baby name. In Celtic the meaning of the name Eoin is: Young. Irish Meaning: The name Eoin is an Irish baby name.In Irish the meaning of the name Eoin is: God is good; God's gift. SoulUrge Number: 2. Expression Number: 7. People with this name have a deep inner desire for love and companionship, and want to work with others to achieve peace and harmony.n Celtic the meaning of the name Eoin is: Young. Irish Meaning: The name Eoin is an Irish baby name. In Irish the meaning of the name Eoin is: God is good; God's gift. SoulUrge Number: 2.