Synonyms of the word 
GAINFUL → PAID - PAYING - PROFITABLE
gainful
- adj. Contrary.
- adj. Disposed to taking advantage of.
- adj. Troublesome; fractious; hard to handle.
- adj. Providing gain; profitable.
paid
- v. simple past tense and past participle of pay.
paying
- v. present participle of pay.
- n. payment.
profitable
- adj. Producing a profit.
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