Sentence:  Holding intercourse with Sir William at this date partook a good deal of the nature of a <WSD>one-handed</WSD> conversation, and the one-handedness seemed to increase when the only share of the host, in the post-prandial conviviality, consisted in passing the decanters, which Sir William was scrupulous to do. 
Meaning of the word marked with <WSD> tags:  Involving the actions of only one person.