What does BIG mean?

adjective

1. above average in size or number or quantity or magnitude or extent“a large city”
2. significant“graduation was a big day in his life”
3. very intense“a bad headache”
4. loud and firm“a big voice”
5. conspicuous in position or importance“a big figure in the movement”
6. prodigious“big spender”
7. exhibiting self-importance“big talk”
8. feeling self-importance“too big for his britches”