In a primary manner; pertaining to the principal of a matter.(adverb)
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Use "principally" in a sentence
"Southland is a colloquial term principally used to refer to Southern California."
"With spare language taken principally from the translations by Robert Fitzgerald and Robert Fagles, and with intricate pencil and watercolor illustrations, Mr. Hinds re-creates Odysseus 'turbulent voyage across "the wine-dark sea" from the ruins of Troy to the island of Ithaca and his long-suffering wife, Penelope."
"This skin is created principally from a glass exterior skin, steel structure, wood decking and grassed, faceted roofscape."