Sources

Cadlock                    1849        OS 6 inch
CÀDLOCH.               1887        Maxwell: 100

CADLOCK – A small thatched House in good repair. it takes its name from a place on the shore. where fishermen takes bait for fishing. OS names book. OS1/35/3/63

Additional Information

Given the description in the OS names book this looks to be cladach with a nonadjacent metathesis. Gaelic Cladach > Scots Cadloch. The shore line here is indeed a ‘cladach’, shingles, rather than a ‘tràigh’, sand and the croft was situated next to the shore.