a blockhead; a dunce; a numskull.-a spherical mass of iron, with a long handle, used to heat tar.-an upright piece of round timber, in a whaleboat, over which a turn of the line is taken when it is running out too fast.-a very large marine turtle (thalassochelys caretta, / caouana), common in the warmer parts of the atlantic ocean, from brazil to cape cod; -- called also logger-headed turtle.-an american shrike (lanius ludovicianus), similar to the butcher bird, but smaller. see shrike.