What is to fashion into groins; to build with groins. The hand that rounded Peter's dome, And groined the aisles of Christian Rome, Wrought in a sad sincerity. Emerson called?

groin — To fashion into groins; to build with groins. The hand that rounded Peter's dome, And groined the aisles of Christian Rome, Wrought in a sad sincerity. Emerson. (Webster's 1913.)

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