Contrivance, n.
1. The act or faculty of contriving, inventing, devising, or planning. The machine which we are inspecting demonstrates, by its construction, contrivance and design. Contrivance must have had a contriver. Paley.
2. The thing contrived, invented, or planned; disposition of parts or causes by design; a scheme; plan; atrifice; arrangement. Government is a contrivance of human wisdom to provide for human wants. Burke.
Syn. -- Device; plan; scheme; invention; machine; project; design; artifice; shift. See Device.
Shades of meaning
Fernald has no entry of its own for contrivance; he lists it under artifice.
Where he writes about it:
A contrivance or device may be either good or bad. — from artifice
Imposture is a deceitful contrivance for securing charity, credit, or consideration. — from artifice
An artifice is a carefully and delicately prepared contrivance for doing indirectly what one could not well do directly. — from artifice
Finesse is especially subtle contrivance, delicate artifice, whether for good or evil. — from artifice