Most unique.
“uniqid,” PHP documentationIf set to TRUE,
uniqid()will add additional entropy (using the combined linear congruential generator) at the end of the return value, which should make the results more unique.
It’s a weird clause. Adding additional entropy already has a highly specific, mathematical meaning, none of which is conveyed by something more unique. In fact, that would probably confuse the people who are not vaguely aware of entropy and cryptography. If it’s set to false, is it less unique? Will it somehow duplicate itself? Existential crisis, existential crisis, et cetera. All well. Without PHP, the English language would just sit there, unmolested by grammatical atrocities like these.