Byzantine Greek vs Medieval Greek language

Byzantine Greek

name

Collectively, the continuum of forms of the Greek language as written and spoken during the time of the Byzantine Empire (C.E. 330–1453), preceded by Koine Greek and Early Medieval Greek and succeeded by Late Medieval Greek to Modern Greek. (ISO 639-3 code: grc shared with Classical Greek.)

Medieval Greek language

How often have the words Byzantine Greek and Medieval Greek language occurred in a corpus of books? (source: Google Ngram Viewer )