Descriptive of swift clinch = CLEVER (refers to Clever Tom Clinch in poem by Jonathan Swift)
SEE
www.online-literature.com/swift/poems-of-swift/62/ -
16D: I'm also 'stuck' and have previously posted a question re this possibly being 'LOOPHOLE'. There is a short story by Arthur C Clarke with this title, but I'm not convinced. So hopefully someone will come to our aid!