a. Obs. rare–1. In 7 cal-. [f. as prec. + -OUS.] Of the nature of ink or blacking.
1646. Sir T. Browne, Pseud. Ep., VI. xii. 337. A Calcanthous or Atramentous quality.
1656. Blount, Glossogr., Calcanthous, pertaining to Shoomakers black or Vitriol.
