different between profitless vs unproductive

English

profit +? -less

profitless (comparative more profitless, superlative most profitless)

not yielding profit
- 1600, Shakespeare, Much Ado About Nothing, [1]:
  I pray thee, cease thy counsel,
  Which falls into mine ears as profitless
  As water in a sieve...

un- +? productive

unproductive (comparative more unproductive, superlative most unproductive)

Not productive; useless; fruitless.
Juggling is an amusing pastime, but generally unproductive.
(linguistics, of affixes, mechanisms of word formation, etc) No longer used to produce new words (see examples).

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