ca' canny
noun
ca' can·ny kȯ-ˈka-nē 
British
: slowdown
ca' canny intransitive verb British
Word History
Etymology
borrowed from Scots, "proceed warily, act cautiously" (imperative and infinitive), from ca' "to call, urge forward, drive, proceed" (Scots form of call entry 1) + canny "warily," from canny, adjective, "prudent, wary" (Scots senses of canny entry 1)
First Known Use
1886, in the meaning defined above