What is an "enlightening being"?

Thomas Cleary uses the term "enlightening being" extensively in his translation of the Avatamsaka Sutra . This term isn't defined in the glossary of that book, or in my copy of The Princeton Dictionary of Buddhism . Is there a canonical definition of "enlightening being"? Edit: Thanks useful comments by @ChrisW and @KayCee, I see in Appendix 1 "bodhisattva or enlightening being". I'm finding it helpful to read this Appendix before returning to the Introduction.