me·chan·i·cal / məˈkanikəl/ • adj. 1. working or produced by machines or machinery: a mechanical device. ∎ of or relating to machines or machinery: a mechanical genius mechanical failure.2. (of a person or action) not having or showing thought or spontaneity; automatic: she stopped the mechanical brushing of her hair.3. relating to physical forces or motion; physical: the smoothness was the result of mechanical abrasion. ∎ (of a theory) explaining phenomena in terms only of physical processes. ∎ of or relating to mechanics as a science.• n. 1. (mechanicals) the working parts of a machine, esp. a car.2. (usu. mechanicals) archaic (esp. with allusion to Shakespeare's A Midsummer Night's Dream) a manual worker: rude mechanicals.3. Printing a completed assembly of artwork and copy, typically mounted on a sheet of stiff paper.DERIVATIVES: me·chan·i·cal·ly adv.me·chan·i·cal·ness n.