verkningslös înseamnă în Engleză

ineffective▼(not having the desired effect; ineffectual)
adjective
[UK: ˌɪ.nɪ.ˈfek.tɪv] [US: ˌɪ.nə.ˈfek.tɪv]Many people don't know that antibiotics are ineffective against viral diseases. = Många vet inte om att antibiotika är verkningslösa mot virussjukdomar.

inefficient▼(incapable of, or indisposed to, effective action)
adjective
[UK: ˌɪ.nɪ.ˈfɪʃnt] [US: ˌɪ.nə.ˈfɪ.ʃənt]