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Webster 1913 Edition

Addendum

‖

Ad-den′dum

,

Noun.

;

pl.

Addenda

.

[L., fr.

addere

to add.]

A thing to be added; an appendix or addition.

Addendum circle

(Mech.)

,

the circle which may be described around a circular spur wheel or gear wheel, touching the crests or tips of the teeth.

Rankine.