Sentence:  ... since few wanted mosaics any more he had turned to fresco, becoming the greatest <WSD>absorber</WSD> and eclectic in Italy. He had learned everything that the earlier fresco painters, from the time of Cimabue, had to teach. 
Meaning of the word marked with <WSD> tags:  A person who absorbs. (First attested in the mid 19th century.)<ref name=SOED/>