Puissant

is read as \PWIS-uhnt\ meaning powerful, mighty, potent

Example1:
Nuclear bomb is a very puissant weapon to wipe out the entire human race.
(I encountered this word in a book on How To Build A Better Vocabulary and since I lack retention I included puissant here to remind me of what it is).

Example2:
Some village people in our locality have always told my husband that the kind of tablet he is recommending for them to take for any kind of pain is very puissant. They used to come and say their thanks in awe.

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