Hibs record their first home league victory with a goal in each half from Garry O'Connor and Steven Fletcher at Easter Road.
The Edinburgh side were worth a more handsome advantage against a United side who had plenty of possession but little punch.
Hibs had more of a cutting edge and snatched the lead with the simplest of goals after 11 minutes.
Chris Innes misplaced a header into the path of the eager Derek Riordan who measured his ball across the face of the goal for O'Connor to slide in his eighth goal of the season.
Hibs always looked dangerous going forward and Riordan was a constant concern to the United defence. The young striker whipped in another low cross midway through the first half but the angle was just too tight for O'Connor to cash in.
Then a long through ball from the assured Steven Whittaker just eluded Riordan as Paul Jarvie collected.
Gary Caldwell found Riordan with another long pass shortly afterwards but the striker's 25-yard shot struck a defender and Jarvie gathered easily.
But it was by no means one-way traffic. United also played some neat football at times even if Simon Brown was well protected.
An Innes header from Barry Robson's cross was just six inches wide of Brown's left-hand post as United fired a warning to Hibs.
The game flared up ten minutes from the break when Robson claimed that Guillaume Beuzelin stamped on him as they challenged for a loose ball and O'Connor then pushed the United man to the ground.
Mike Ritchie flashed the yellow card at O'Connor and Robson.
Five minutes from the break, Riordan almost snatched a breathtaking goal. O'Connor sought him out with a 40-yard pass and he somehow managed to flick the ball over the onrushing Jarvie from 16 yards but the ball bounced just wide.
Fletcher should have made it 2-0 two minutes into the second half but sent his six-yard header over from a Riordan corner.
Then Riordan sliced a shot wide when he had time to do better after a Fletcher header broke to him.
The goal was only delayed as Fletcher notched his first goal for the club when he took a pass from O'Connor to drill home a left-foot shot.
United had chances to come back into the game and Simon Brown saved well from Derek McInnes before substitute Jason Scotland shot narrowly wide from long range.
The best chance fell to Alan Archibald in the closing stages but he somehow headed wide from five yards from a Mark Wilson corner.