From the root ag or ac is produced by a phonetic termination the form agin or akin.  The only appellatives that I find are the Old High Germ. agana, Goth. ahana, Old Norse ögn, stalk, stem, spike, North Eng. awn, the beard of barley, from which we may assume for proper names the meaning of spear or weapon. (The Teutonic Name-System &c., Ferguson, 1864).

    The name is either from hagr, deft or handy, or else from hagi, a hook; most probably the latter, perhaps in connection with the other meaning, a thorn or prickle, so that here we may find a personification of the thorn destroying the victor. (See Haghen and Hagano).  The word hag is seldom found in names, and is probably imitated from Hagen, without much regard to the meaning.  It occurs only in the Danish, as Hagbrand, Hagbart, contracted as Habaar, or Habor; Hagthor, which is incorrectly modernized as Hector; and Hagny.  The more usual form in Denmark is Hogne, probably from the German Hagano. (History of Christian Names, Yonge, 1884)