verb.
To steal in small quantities, or articles of small value; to practise petty theft.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
verb.
make off with belongings of others
Word Usage
"If I had wanted to 'pilfer' your correspondence, which was with me for some ten years, would it not have been easier (and more discreet) for me to make photocopies of the letters I wanted to keep and send you back all your originals intact?"