Originally meaning a servant, the term was applied from the late 9c to members of the AS aristocracy, whose *wergeld was 1,200s. In Latin texts they were called ministri, which carries the same connotations. The standing of a thegn depended on that of his lord: one who served the king was a king's thegn; one who served a lord other than the king (i.e. bishop, abbot, earl or greater thegn) was a median (i.e. middling) thegn. All were noble and outranked the *ceorl; distinctions between them were marked by the amount due as *heriot. Duties of the median thegn were set out in *Rectitudines Singularum Personarum: 'The law of the thegn is that he be entitled to his bookright, and that he shall contribute three things in respect of his land: armed service, and the repairing of fortresses and work on bridges [the *trimoda necessitas]. Also in respect of many estates, further service arises on the king's order such as service connected with the deer fence [*deorhege] at the king's residence, and equipping a guardship, and guarding the coast, and guarding the lord, and military watch, almsgiving and church dues, and many other things.' Such duties were owed by the king's thegn to the king himself. The latinised forms are tainus, teignus. [< OldEngl. degen = servant, follower] -
Cf. Tainus regis
Dictionary of Medieval Terms and Phrases. Christopher Coredon with Ann Williams.