Oscar Tabarez completely changed his starting line-up for their encounter with the Toa Aito and the Palermo striker took full advantage to propel la Celeste into the final four
Abel Hernandez opened the scoring with the fastest goal in the competition's history after 79 seconds and a Diego Perez finish came between his other two strikes which ensured the South Americans took a four-goal lead into half time.
Andres Scotti missed a penalty early in the second half and was then sent off for a second yellow card one minute later, while Teheivarii Ludivion was also shown red for the Oceania champions before Nicolas Lodeiro, Hernandez with his fourth, and a Luis Suarez double wrapped up the win in comfortable fashion.
Having conceded 10 against Spain, Tahiti could not even keep la Celeste out for two minutes, despite the much-changed line-up from the 2-1 win over Nigeria. Lodeiro's corner was flicked on by the unmarked Scotti and Hernandez was also free to head home at the back post, and Uruguay were able to sit back a little having secured their early advantage.
Having denied Walter Gargano and Gaston Ramirez, there was little Gilbert Meriel could do to stop Hernandez from adding his second with 23 minutes on the clock. The Palermo striker exploited the static Tahiti defence, running in behind on to a ball over the top and looping it over Jonathan Tehau before volleying into the back of the net.
Four minutes later they had their third. Perez was the next player to spring the offside trap, getting his head on Gargano's cross and tapping home from close range after his initial nod hit the post.
Uruguay stepped off the gas again and Tahiti took the opportunity to get forward, but Marama Vahirua and Steevy Chong Hue were unable to make the most of the chances that came their way.
Any momentum gained was taken away in first-half stoppage time, though, as Gargano released Hernandez with a cutting pass and the striker poked the ball into the bottom corner to complete his hat-trick.
After the interval it looked as though Oscar Tabarez's men would add their fifth goal when the referee pointed to the spot in the 50th minute following Nicolas Vallar's foul on Matias Aguirregaray, but things did not go to plan.
Veteran Scotti was handed the responsibility of the spot kick but his weak effort was saved by Meriel and one minute later the centre-back was shown a second yellow card following a foul on Chong Hue, reducing la Celeste to 10 men.
The referee evened the sides up in the 59th minute when he dismissed Ludivion for his second bookable offence and the South Americans soon added their fifth. Gargano was again the supplier, drilling a low cross into the area which Lodeiro tapped in from inside the six-yard box.
Hernandez added his fourth with 23 minutes remaining as he showed unerring composure to slot home from the spot after Chong Hue had felled Aguirregaray inside the box.
Meriel denied Hernandez the record of becoming the first player to score five goals in a single Confederations Cup game with a great save, but substitute Suarez was not to be kept out eight minutes from time as he turned Henri Caroine inside out and rolled the ball into the bottom corner.
Suarez then added his second with a tidy finish from the top of the box in the final minute of normal time, becoming Uruguay's all-time highest-scoring player in the process with 35 goals.
Uruguay's win sees them finish second in Group B, setting up a semi-final encounter with hosts Brazil. Tahiti, meanwhile, held up a banner to thank their hosts after the full-time whistle, and will return to French Polynesia having won the hearts of both the host nation and the watching world with their efforts during the tournament.