digit/number: at least almost-all of; at least almost-certain; 100%.
The complementary set is of measure 0 and may even be empty. Often, when people say "100%", they mean "pi ro"; however, "pisoi'ai" is also possible, but is mutually exclusive with the previous possibility (in the same way that "re" cannot mean "su'o re"). This cmavo string covers both cases and, so, is basically equivalent to "piro jonai pisoi'ai". See also: "soi'ai", "piro", "pa", "pisu'esoi'au".