The Collaborative International Dictionary of English v.0.48:
blueing \blue"ing\ n. Same as bluing. [PJC]WordNet (r) 3.0 (2006):
blueing n 1: used to whiten laundry or hair or give it a bluish tinge [syn: bluing, blueing, blue] 2: a process that makes something blue (or bluish) [syn: bluing, blueing]