Synonyms for Working (same or very similar meaning)
WordNet sense 1 (a mine or quarry that is being or has been worked):
workings
WordNet sense 2 (concerned with actual use or practice):
practical
WordNet sense 3 (not permanent; not lasting):
impermanent, temporary
WordNet sense 4 ((of e.g. a machine) performing or capable of performing):
functional, running
WordNet sense 5 (performing or able to perform its regular function):
functioning
WordNet sense 6 (actively engaged in paid work):
on the job
WordNet sense 7 (having your services engaged for; or having a job especially one that pays wages or a salary):
employed
WordNet sense 8 (being in force or having or exerting force):
operative
From the ODE community, based on WordNet
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