59. Feminine nouns corresponding to distinctly masculine nouns such as
"frato", "knabo", "viro", may be formed from these by inserting the
suffix "-in-" just before the noun-ending "-o":
fratino = sister patrino = mother
(from frato, brother). (from patro, father).
knabino = girl virino = woman
(from knabo, boy). (from viro, man).
[Footnote: Cf. English names similarly formed from masculine names,
as "Pauline, Josephine, Ernestine, Geraldine," etc., also German
"Koenigin", queen, from "Koenig", king; "Loewin", lioness, from "Loewe",
lion, etc.]