If you say that something is a reality check for someone, you mean that it makes them recognize the truth about a situation, especially about the difficulties involved in something they want to achieve.
This first reality check for the players could shape the rest of the club's season. [+ for]
reality check in British English
noun
an occasion or opportunity to consider a matter realistically or honestly
reality check in American English
an instance of confronting or acknowledging the facts about something and thus dispelling unrealistic notions
Examples of 'reality check' in a sentence
reality check
This is the reality check your husband needs.
Times, Sunday Times (2017)
What she really needs is a reality check.
The Sun (2015)
We need a reality check on these reality shows.
The Sun (2009)
Bosses thought he needed a reality check.
The Sun (2011)
But dealing responsibly with these anxieties needs some reality checking and some scrutiny of the mythology of panic.
Times, Sunday Times (2009)
This was a bit of a reality check and shows just how much work we still have to do.
The Sun (2012)
The church needs a reality check.
Christianity Today (2000)
Unlikely, you might say but a reality check may manifest itself.
Times, Sunday Times (2008)
Let's just take a reality check on that.
The Sun (2016)
When it comes to the future of energy, the world needs a reality check.
Times, Sunday Times (2007)
Under present circumstances, we need a national reality check.
Times, Sunday Times (2011)
I needed constant reality checks along the way.
The Sun (2009)
You need a reality check.
The Sun (2014)
But it was the reality check I needed to give up the job.
The Sun (2009)
But musically she needed a reality check and, thankfully, this is it.
The Sun (2008)
My mother was right: my generation are a bunch of self-absorbed brats who need a reality check.
Times, Sunday Times (2006)
And that, more than any set of accounts, is a sign of the financial reality check hitting football.