Word Study
fils (root: fil)
CIDE DICTIONARY
fils, n. [F., fr. L. filius. See Filial.].
Son; -- sometimes used after a French proper name to distinguish a son from his father, as, Alexandre Dumas, fils. [Webster 1913 Suppl.]
OXFORD DICTIONARY
fils, n. (added to a surname to distinguish a son from a father) the son, junior (cf. P
Usage
RE).
Etymology
F, = son
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