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"oppose" is also used as a crossword clue. If that's what you saw, the answer is often resist (6 letters).
Definitions
be against; express opposition to
Word origin
From Middle English opposen, from Old French opposer, from Latin ob (“before, against”) + Medieval Latin pono (“to put”), taking the place of Latin opponere (“to oppose”).
Used in a sentence
“to oppose the king in battle”
“to oppose a bill in Congress”
“There is still time to oppose this plan.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Be against”6 letters
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