What is etym: [Cf. F. arbre.] (Mech.) (a) An axle or spindle of a wheel or opinion. (b) A mandrel in lathe turning. Knight. Arbor Day, a day appointed for planting trees and shrubs. [U.S.] called?

arbor — Etym: [Cf. F. arbre.] (Mech.) (a) An axle or spindle of a wheel or opinion. (b) A mandrel in lathe turning. Knight. Arbor Day, a day appointed for planting trees and shrubs. [U.S.]. (Webster's 1913.)

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