act out

[Jonathan Lighter]

Not in OED (if you can believe it).  It's been in popular as well as
psychological use for decades.

But never mind that.  In discussing the recent incident at SeaWorld, an
animal expert on CNN talked about the likelihood that any captive killer
whale could begin to "act out" at any time.

Just how an animal might "act out" in human psychological terms I don't
know. I suppose I would have said, "revert to type," "become enraged," "harm
its trainer," "turn," etc., long before it would have occurred to me to say
"act out."

"Act up," of course, is far too mild to adequately cover what happened.

JL
--
"If the truth is half as bad as I think it is, you can't handle the truth."

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