noun: (obsolete) Late Old English and early Middle English, perceived as a language intermediate between Anglo-Saxon and English and belonging to the period from 1100 to 1200/1230/1250 (depending on author).
adjective: (obsolete) Relating to Late Old English and early Middle English, the form of the English language belonging to the period from 1100 to 1200/1230/1250 (depending on author).