Note
This guy is so big that everywhere he goes, there's only space for one person.
Usages of big
A dog is basically just a big dot running around.
Heaven is one hell of a big place.
You have a big gun that shoots arrows.
There's a new type of book, with each page made from big grains of rice.
A big sheep teaches you the true meaning of beauty.
The people in the center of power always cover up big things.
When you're curious, even big things become possible.
A calamity bends our life in a big way.
Even if you bend the upside down box, the rice is simply too big to fit in its interior.
You carve a big mark as a sign of your pledge.
大きさ is more general than サイズ. For shoes, clothes and other items that come in standardized sizes, it's more common to hear サイズ.
You have a big archery glove.
Grass must not be in the sun too much until it is big.
Your enclosure plays a big factor in your contentment.
You participate privately in big hair festivals.
