addĭtĭo

ōnis, f.

id.

I. an adding to, addition: figurarum additio et abjectio, Quint. 9, 3, 18: Sic corpori fit additio, Cael. Aur. Acut. 2, 37; Prisc. p. 978 P.
Lewis & Short
A Latin Dictionary, 1879
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