Are these two adjective definitely interchangeable and equivalent at all times?If I were to describe a person's characteristic, which kne would more appropriate?Thanks in advance;)
No two adjectives are definitely interchangeable and equivalent at all times.*

'He is downright dishonest.'

'He is an outright narcissist.'

[* I expect somebody will find two which are.]

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Rover,So, out of my own guess, "outright" is usually collocated before a noun wheres "downright" usually before an adjective?
What if it's a verb? Like 'ban'.
When used as an adjective:
  • outright is closer in meaning to "complete" or "unquestionable" or "utter"
  • downright is probably closer to "extreme".
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I'm thinking that outright comes with the connotation of being obvious or public, while downright calls for a conclusion to be drawn.