the GNU version of the Collaborative International Dictionary of English
n. The act of besetting, or the state of being beset; also, that which besets one, as a sin.
The Century Dictionary and Cyclopedia
n. The state or condition of being beset.
n. The sin or failing to which one is most liable; a besetting sin or tendency.
Word Usage
"The man's abiding obsession -- if we may call his besetment thus -- changed in practically all essential regards the manners and the practices of his daily life."