tough cookie

クッキー（cookie）は食べ物、お菓子の1種ですね。

その”cookie”は人を指すのに用いられることがあります。女性ならば、恋しい人に対する愛情を込めた呼び掛けとして、男性に対しては、これも親しみを込めて、奴（やつ）といった具合です。


President Trump hosted his third wide-ranging rally of the midterm season in Montana on Thursday night, where he urged voters to "never forget Benghazi" and praised Republican Rep. Greg Gianforte, who pleaded guilty to body slamming a reporter last year, as a "tough cookie."
(Trump praises 'tough cookie' Montana rep who 'body slammed' reporter last year, urges voters to 'never forget Benghazi.’ Fox News. October 19, 2018.)


引用した記事に使われている、


tough cookie


とは、タフな奴、タフガイ、頑張り屋さん、といったくらいの意味になるようです。

ちなみに、”smart cookie”という言い回しもあります。


Even as he talks tough on North Korea, Trump called Kim Jong Un a "smart cookie" and wondered why he won't be his friend.
(USA Today, 2017)


“smart cookie”は賢い奴、くらいになるでしょうか。

“bad cookie”というのもあります。


They didn't like what he did to the kids so they padded up the charges. We're going to file multiple charges. We get him on one of them. That's what happens. I mean, this guy is a bad guy. He's a bad cookie.
(2013)