The mechanisms that function internally to a system and are not outwardly visible

(nautical) Any of the sails which are used in most kinds of weather: mainsail, foresail, jib and/or mizzen. Sometimes referred to as the lowers.

plural of workingman

Alternative spelling of working-class

The social class of those who perform physical work for a living, as opposed to the professional or middle class, the upper class, or others.

(usually in the plural) Operation; action. / Method of operation. / (arithmetic) The incidental or subsidiary calculations performed in solving an overall problem. / Fermentation.

present participle of work

That is or are functioning. / That suffices but requires additional work. / In paid employment. / Of or relating to employment. / Enough to allow one to use something. / Used in real life; practical.

A knowledge of how to make something work without deeper theoretical understanding of why it works.

A definition that is chosen for an occasion and may not fully conform with established or authoritative definitions.