This is the 878th most frequent Croatian word.
velike
"Velike" means "big" or "large" in English (feminine plural form).
In this case, 'velike' is an adjective modifying 'rijeke' (rivers), again agreeing in gender and number.
Velike rijeke obično teku kroz nizinske krajeve.
Big rivers usually flow through lowland areas.
Here, 'velike' is an adjective in the plural form used to describe 'planove' (plans), matching its gender and number.
Imam velike planove za budućnost.
I have big plans for the future.
'Velike' here describes 'zgrade' (buildings), showing its use as an adjective consistent with the nouns it modifies.