As nouns the difference between moa and giraffe

is that moa is a very large, extinct, flightless bird of the family Dinornithidae that was native to New Zealand; until its extinction, one species was the largest bird in the world while giraffe is a ruminant, of the genus Giraffa, of the African savannah with long legs and highly elongated neck, which make it the tallest living animal; yellow fur patterned with dark spots, often in the form of a network; and two or more short, skin-covered horns.

As an acronym MOA

is minute of angle.