Big Difference
noun
違い is difference, so a big one of those is a big difference.
The reading is 違い plus 大 of 大きい (おお) put together. You can remember this because when you see the difference (the BIG difference), you say "oohhhhh" (お), because you were surprised you didn't see it before.
やっぱり、聞くと見るでは大違いだね。
Certainly, there's a big difference between hearing and seeing, isn't there?
ホットケーキにメープルシロップをかけるのとかけないのとでは大違いだよ。
It makes a big difference whether or not you pour maple syrup over a pancake.
山田さんのご主人は私の夫とは大違いだ。
Yamada-san's husband is very different from my husband.
堅い木の椅子と柔らかい快適な椅子じゃあ大違いだよ。
There is a big difference between a hard wooden chair and a soft cushy chair.