[æb'stru:sәti]
n.
难解, 深奥

[ noun ]
wisdom that is recondite and abstruse and profound
<noun.cognition>
the anthropologist was impressed by the reconditeness of the native proverbs

Abstrusity \Ab*stru"si*ty\ ([a^]b*str[udd]"s[i^]*t[y^]), n.
Abstruseness; that which is abstruse. [R.] --Sir T. Browne.