Is there any difference between "anyone" and "any one"?

Solution 1:

The Oxford English Dictionary (OED) states regarding any one:

"The two-word form any one is not the same as the one-word form anyone and the two forms cannot be used interchangeably. Any one means ‘any single (person or thing)’, as in: not more than twelve new members are admitted in any one year."

Meanwhile, the one word form anyone is defined as follows:

anyone

Line breaks: any¦one Pronunciation: /ˈɛnɪwʌn/

Definition of anyone in English: pronoun

1 [USUALLY WITH NEGATIVE OR IN QUESTIONS] Any person or people: there wasn’t anyone there does anyone remember him? I was afraid to tell anyone

1.1 [WITHOUT NEGATIVE] Used for emphasis: anyone could do it

2 A person of importance or authority: they are read by anyone who’s anyone