The Collaborative International Dictionary of English v.0.48:
Expurgatory \Ex*pur"ga*to*ry\, a. [Cf. F. expurgatoire.] Serving to purify from anything noxious or erroneous; cleansing; purifying. "Expurgatory animadversions." --Sir T. Browne. [1913 Webster] Expurgatory Index. See Index Expurgatorius, under Index. [1913 Webster]