Primarily means "is hard", physically. Compare to 'ewily, "rock".
Can also mean, "hardens, becomes hard" and "is firm, stiff".
It would be interesting to know if the double meaning of "is difficult" is coincidental or due to influence from Spanish or English. Tiipay has verb llypiiwarr "it is difficult, hard to do", and 'Iipay related noun kullypiiwarp "things that are hard to do", from verb llyepuuwar (llyepechewar) "is unable, can't do it", yet Tiipay also has verb wirr, equivalent of 'Iipay 'ewir with the exact same meaning.