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hijo (Noun) "son," "daughter"
11th cent. Old Spanish fijo. From Latin filius 'id.,' Old Latin filios. From Proto-Italic *filio- 'id.' From Proto-Indo-European *dhh1i̯-l- 'id.' From *dheh1- "to suckle." See also felíz.
Indo-European
Romance
Asturian fíu, Portuguese fillo, Galician fillo, Catalan fill, French fils, Italian figlio, Aromanian hilj, Romanian fiu, Sardinian fidzu, fillu
Italic
Umbrian fel, Faliscan fileo, Venetic filia "daughter"
Messapian
Messapian bilia "daughter"