仕様
しよう · shiyou · JLPT N3 · noun
manner
📋 仕 do + 様 manner = the manner of doing it: the method or spec
仕 means to serve or do, and 様 means way or manner. Put together, it's how something is done, which is why engineers use it for a spec. It's also in the set phrase 仕様がない (shiyou ga nai): there's no way, it can't be helped.