upirati

1. (finger, gaze + u + acc.) to point at; to fix one's gaze on
   Svi upiru prstom u vladu zbog krize. — Everyone is pointing the finger at the government over the crisis.
   Zašto stalno upireš pogled u mene? — Why do you keep staring at me?
2. (o + acc., u + acc.) to push against; to brace against
   Upirao je ramenom u vrata da ih otvori. — He was pushing against the door with his shoulder to open it.
3. (upirati se) to strain; to make a great effort
   Upirao se iz sve snage, ali orman se nije pomerio. — He strained with all his might, but the wardrobe didn't move.

The perfective in standard ekavian is upreti.