  We find the asymptotic formula for quasinormal mode frequencies omega_n of
the Dirac equation in a Schwarzschild-AdS_D background in space-time dimension
D > 3, in the large black-hole limit appropriate to many applications of the
AdS/CFT correspondence. By asymptotic, we mean large overtone number n with
everything else held fixed, and we find the O(n^0) correction to the known
leading O(n) behavior of omega_n. The result has the schematic form omega_n =~
n Delta(omega) + A ln(n) + B, where Delta(omega) and A are constants and B
depends logarithmically on the (D-2)-dimensional spatial momentum k parallel to
the horizon. We show that the asymptotic result agrees well with exact
quasinormal mode frequencies computed numerically.
