if (one's) a day(redirected from if they're a day)
if (one's) a day
One is at least a particular age (which is typically specified right before this phrase is said). Stu's been with the company for almost 30 years, so I bet he's 50 if he's a day.
if one's a day
Fig. a phrase attached to an expression of someone's age. She's fifty if she's a day! I'm sure he's forty-five if he's a day.
if one’s a day
phr. a phrase attached to an expression of someone’s age. I’m sure he’s forty-five if he’s a day.