vas aberrans of Haller

noun

vas ab·​er·​rans of Hal·​ler -ˈab-ə-ˌranz-əv-ˈhäl-ər 

plural vasa aberrantia of Haller -ˌab-ə-ˈran-ch(ē-)ə- 

: a blind tube that is occasionally present parallel to the first part of the vas deferens and that may communicate with the vas deferens or with the epididymis

called also ductulus aberrans