per`spi*ca"cious*ness
Webster's Dictionary (GCIDE)
Perspicacious \Per`spi*ca"cious\ (p[~e]r`sp[i^]*k[=a]"sh[u^]s), a. [L. perspicax, -acis, fr. perspicere to look through: cf. F. perspicace. See Perspective.]
1.Having the power of seeing clearly; quick-sighted; sharp of sight. [1913 Webster]
2.Fig.: Of acute discernment; keen. [1913 Webster] -- Per`spi*ca"cious*ly, adv. -- Per`spi*ca"cious*ness, n. [1913 Webster]