köken: Inherited from Late Latin duplāre, a verb based on Latin duplus (“double”, adj.). Compare Portuguese dobrar, Italian doppiare, and French doubler (whence English double).
aile: dobladura, doblaje, doblamiento, doblar el espinazo, doblar la cabeza, doblar la calle, doblar la esquina, doblar la hoja, doblar la llave, doblar la parada
köken: Equivalent to duo (“two”) + -plex (“-fold”). Possibly inherited from Proto-Italic *dupleks, if Umbrian 𐌕𐌖𐌐𐌋𐌀𐌊 (tuplak) is cognate (however, its meaning is uncertain and its form poses some difficulty). The Italic form may be an analogical alteration (with the du- of duo replacing *dwi-) of an original Proto-Indo-European *dwi-pleḱ-s; compare Ancient Greek δίπλαξ (díplax).
aile: duplicō
Duplex omnīnō est iocandī genus, ūnum illīberāle, petulāns, flāgitiōsum, obscēnum, alterum ēlegāns, urbānum, ingeniōsum, facētum.
From Old Galician-Portuguese, from Latin dūplus or duplex (or a derivative of them). Compare Portuguese dobro. For the final '-e' instead of '-o', see Spanish doble.