outside (one's) ken

outside (one's) ken

Advanced beyond one's ability to understand or make sense of the subject matter or task at hand. The stuff they're teaching in this advanced math class is outside my ken.
See also: ken, outside

beyond/outside your ˈken

(old-fashioned) not within your knowledge or understanding: Such things are beyond my ken.
Ken is an old word for ‘knowledge’.
See also: beyond, ken, outside