A garner was originally a granary, and to garner something is to gather it in. Today the word rarely has to do with agriculture: we garner attention, praise, awards, evidence, and sympathy.
To garnish something is to decorate it. You can garnish a pork chop by placing a sprig of rosemary next to it. Quite a few people use “garnish” when they should be using “garner.”
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