noun, noun which may take the genitive case particle 'no', na-adjective
huge sum; enormous amount; massive amount of money
Most often used for very large amounts of money. It can function as a noun or before another noun, commonly as 巨額の; 巨額な is also possible but tends to sound more descriptive or written.
その事業には巨額の費用がかかる。
That project will cost an enormous amount of money.
会社は巨額の損失を出した。
The company posted huge losses.
被害額は巨額に上った。
The amount of damage reached a massive sum.
Means high-priced or involving a high amount; it focuses on price or cost being high, while 巨額 emphasizes the sheer size of the total sum.
A Sino-Japanese compound: 巨 means 'huge' or 'great,' and 額 here means an amount or sum. The spelling transparently reflects the meaning 'huge amount.'