Word Origin & History
dad
recorded from 1500, but probably much older, from child's speech, nearly universal and probably prehistoric (cf. Welsh tad, Ir. daid, Czech, L., Gk. tata, Lith. tete, Skt. tatah all of the same meaning). Daddylonglegs is from 1814; daddy-o is first recorded 1949, from bop talk.