loggerhead

1. (obsolete) A stupid person; a blockhead, a dolt.Examples: "Ah, you whoreſon loggerhead, you were borne to do me ſhame."; "[Y]ou in the mean time, you ſilly Logerhead, deſerve to have your Bones well-thraſh'd with a Fool's ſtaff, for thinking to ſtir up Kings and Princes to War by ſuch Childiſh Arguments."Synonyms: addle-brain, addlehead, addle pate, airhead, baboon, beanbrain, beetlebrain, beetleheadobsolete

2. (nautical) A post on a whaling boat used to secure the harpoon rope.Examples: "Not very far distant Flask's boat was also lying breathlessly still; its commander recklessly standing upon the top of the loggerhead, a stout sort of post rooted in the keel, and rising some two feet above the level of the stern platform. It is used for catching turns with the whale line. Its top is not more spacious than the palm of a man's hand, and standing upon such a base as that, Flask seemed perched at the mast-head of some ship which had sunk to all but her trucks. But little King-Post was small and short, and at the same time little King-Post was full of a large and tall ambition, so that this loggerhead stand-point of his did by no means satisfy King-Post."

3. (Midlands, dialectal, often in the plural) A thistle-like flowering plant of the genus Centaurea, particularly the common knapweed (Centaurea nigra).Examples: "Loggerheads, from the resemblance of its knobbed involucres to a weapon so called, consisting of a ball of iron at the end of a stick, the knapweed, the Clobbewed of old MSS. Centaurea nigra, L."; "Bolwes, loggerheads, centaurea nigra. […] Bolwes is balls, the hard round heads of the wort. Loggerheads is a name I have often heard in Oxfordshire."Midlandsdialectalin-pluraloften