事無し, ことなし
'ku' adjective (archaic), Archaism
1. uneventful, peaceful, safe
2. easy, simple
NA-adjective
3. having nothing to do
に
Particle
1. at (place, time), in, on, during
2. to (direction, state), toward, into
3. for (purpose)
4. because of (reason), with
5. by, from