What is the synonym of hudge?

"Huge" is a very common word, so there are quite a few synonyms depending on the context. Here are some options, ranging from formal to informal:

Formal:

* Enormous

* Immense

* Vast

* Colossal

* Gigantic

* Monumental

* Tremendous

Informal:

* Massive

* Giant

* Big

* Gargantuan

* Whopping

* Humongous

More specific synonyms:

* Extensive (for size or scope)

* Voluminous (for quantity)

* Bulky (for physical size)

The best synonym for "huge" will depend on the specific context and the desired level of formality.