sb. and adv. [lit. = bare shirt, in reference to a current etymology of BERSERKER, q.v.] A. sb. (also attrib.) A BERSERKER, or wild Norse warrior; sometimes explained as a warrior fighting in his bare shirt. B. adv. In a shirt only, without armor.
1840. Carlyle, Heroes, vi. The great savage Baresark.
1857. Emerson, Poems, 187. Thy sires Failed to bequeath The Baresark marrow to thy bones.
1866. Kingsley, Herew., xii. 169. I will go baresark to-morrow to the war.