Sentence:  The absence of trust is sometimes called <WSD>untrust</WSD> (Marsh and Dibben, 2005). As most of the trust literature focuses on the positive aspect of trust, it is restricted to the simple dichotomy between trust and <WSD>untrust</WSD>. 
Meaning of the word marked with <WSD> tags:  Lack or absence of trust; mistrust; distrust.