The Collaborative International Dictionary of English v.0.48:
Canker \Can"ker\ (k[a^][ng]"k[~e]r), v. t. [imp. & p. p. Cankered (-k[~e]rd); p. pr. & vb. n. Cankering.] 1. To affect as a canker; to eat away; to corrode; to consume. [1913 Webster] No lapse of moons can canker Love. --Tennyson. [1913 Webster] 2. To infect or pollute; to corrupt. --Addison. [1913 Webster] A tithe purloined cankers the whole estate. --Herbert. [1913 Webster]