Engelhard
German: variant of Engelhardt.
Dictionary of American Family Names, Oxford University Press, ISBN 0-19-508137-4
Engelhardt
German: from a Germanic personal name composed of the elements engel (see Engel) + hard ‘brave’, ‘hardy’, ‘strong’.
Dictionary of American Family Names, Oxford University Press, ISBN 0-19-508137-4
Engelhart
Dutch and German: variant of Engelhardt.
Dictionary of American Family Names, Oxford University Press, ISBN 0-19-508137-4