Definition of infangthief in US English:

infangthief

noun

historical
  • (in Anglo-Saxon law) the right of the lord of a manor to try and to punish a thief caught within the limits of his demesne.

    • ‘Barony jurisdiction included infangthief, the right to try a thief found with the stolen goods still on him.’
    • ‘Infangthief was another outgrowth of the personal vengeance system, the right of vengeance being transferred to the government.’

Origin

Old English infangenthēof ‘thief seized within’.

Pronunciation

infangthief

/ˈinfəNGˌTHēf/