Not frederik, frederig, frederic, fridrik, bedřich, bedříšek, béda, frede, frederick, frits, freek, freerk, rik, fedde, fedrîgh, fredrick, freddy, fredric, priidu, priit, priidik, preedik, reedik, fríðrikur, fredrik, veeti, riete, frédéric, friedrich, fritz, fredi, fredy, feick, freideríkos, frigyes, frici, friðrik, feardorcha, federico, fredo, federigo, fridericus, frīdrihs, fricis, frīdis, freds, fredijs, frederiks, frederikas, frethirik, friðríkr, fryderyk, fredek, fryc, fradique, frederico, fridrih, freadaraig, friderik, fico, feche, ffredig, ffred, alfred, alfredo, elfreda, freda, fredie, wilfred, wilfredo, winfred, winifred, or manfred.

Just fred. freddie also accepted.