Synonyms of astronomical

1 Syllable

vast

2 Syllables

monster, vaster, stellar, whopping, jumbo, spread-out, epic, mammoth, mega, vastest

3 Syllables

tremendous, sizeable, galactic, pandemic, humongous, enormous, ginormous, gigantic, stretched-out, prodigious, colossal, massive

4 Syllables

monumental, universal, astronomic

5 Syllables

considerable