This is the 12348th most frequent Turkish word.
havuzu
"The pool" (definite accusative or possessive form of "havuz").
The word 'havuzu' refers to the direct object 'the pool', as indicated by the accusative suffix '-u' suggesting specificity.
Çocuklar havuzu temizliyor.
The children are cleaning the pool.
Here, 'havuzu' is used to denote the direct object 'the pool' being seen, emphasized by the presence of the relative clause before it.
Havuzu gören herkes çok beğendi.
Everyone who saw the pool liked it very much.
In this sentence, 'havuzu' is part of the possessive construction 'big pool of the house', showing possession along with descriptive context.