大きい is big, and 大きさ is size.
This happens with some other qualitative adjectives:
An easy example would be 長い (long) and 長さ (length) or 高い (high) and 高さ (height).
This could help you relate those two.
大きい is big, and 大きさ is size.
This happens with some other qualitative adjectives:
An easy example would be 長い (long) and 長さ (length) or 高い (high) and 高さ (height).
This could help you relate those two.