not well known (Oxford)
difficult to understand (Oxford)
not known to many people (Cambridge)
to prevent something from being seen or heard (Cambridge)
to make something difficult to discover and understand (Cambridge)
The origins of the tradition have become obscure. (Oxford)
I found her lecture very obscure. (Oxford)
Managers deliberately obscured the real situation from federal investigators. (Cambridge)
His answers were obscure and confusing. (Cambridge)
obscure traditions
obscure lecture
obscured the real situation
answers were obscure
Ambiguous
vague
Clear
Obvious
Obscure