Online slots use familiar words like wild, scatter, and payline in unique ways...

https://city-wiki.win/index.php/What_Does_It_Mean_When_a_Wild_Covers_a_Whole_Reel%3F

Online slots use familiar words like wild, scatter, and payline in unique ways that can affect your gameplay. For example, a wild can substitute symbols to create wins, while a scatter may trigger bonus rounds