The Collaborative International Dictionary of English v.0.48:
Pillared \Pil"lared\, a. Supported or ornamented by pillars; resembling a pillar, or pillars. "The pillared arches." --Sir W. Scott. "Pillared flame." --Thomson. [1913 Webster]WordNet (r) 3.0 (2006):
pillared adj 1: having pillars; "the pillared portico"