Le Pamplemousse said:
"Explain away" is never used in that way.
"so you can explain it in better words" would be correct.
Really?
To explain something away means to rationalize your way out of something you've said or done, when problematic evidence is placed before you.
You maintain that the world was created in 4572 BC. I show you fossils, give you material about carbon dating, set a stack of scientific research in front of you-- and I say, "explain
that away."
You're joking with a bunch of your friends about what an ugly troll Judith is. Then you notice her best friend is sitting in the next booth, regarding you as she might an inchworm. You stammer and temporize, you parse the meaning of "ugly troll" and, as an afterthought say-- oh! You thought I meant
that Judith! I meant the one in the Caravaggio painting, cutting off Holofernes's head with a dull sword! You have trouble talking around that foot you stuck in your mouth, though, you've insulted your friend, and your lame attempts to explain it away are getting you nowhere.
Clinton had his story down perfectly, and had all sorts of corroboration-- but he couldn't explain away that incriminating spot on the dress.
In idiomatic English we also say to waffle, to backpedal, to grasp at straws, and to try and weasel your way out of something you've said.
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