sveznajuć

1. formal omniscient; all-knowing
   Bog je u mnogim religijama sveznajuć i svemoguć. — In many religions God is all-knowing and almighty.
   U romanu je sveznajući pripovedač. — The novel has an omniscient narrator.
2. ironic (of a person) know-it-all
   Nervira me njegov sveznajući ton, a i on ponekad greši. — His know-it-all tone annoys me, and he makes mistakes too.

The definite form sveznajući is more common; the indefinite sveznajuć is used mainly predicatively. A know-it-all person is usually called by the noun sveznalica.