Myrtaceae: Syzygium nervosum DC.: 2 high res. images.
synonyms: Cleistocalyx operculatus (Roxb.) Merr. & L.M.Perry, Eugenia operculata Roxb., Syzygium operculatum (Roxb.) Nied.
location/date (both): University of Agricultural Sciences campus, Bangalore, July 1997
I am yet to find as to how to differentiate it from widely variable
https://efloraofindia.com/2011/04/01/syzygium-cumini/
Maybe … can clarify as to what it can be ?
Syzygium operculatum
Ok, I’ll check it out and get back to you. I am on a field trip now