Locked Wilds is a feature available in some video slots at online casinos. Usual Wild symbols have wildcard function and can replace all other symbols. If, for example, you have two symbols that are the same on one row and the third symbol is a Wild you will get the win that is calculated for three symbols on a row.
Locked Wilds works the same way but the Wild symbols that you receive are locked down. Spin the wheel again and the other symbols are replaced with new ones. This means that there are plenty of chances to win when you play video slots with Locked Wilds.