Spurs were in command throughout the contest at White Hart Lane, but it took a first club goal from full-back Trippier to seal all three points and a fourth consecutive league victory.
It means Tottenham climb a point above Manchester City in the table and now sit five behind league leaders Leicester.
Mauricio Pochettino's men took to the field shortly after Leicester had secured a stunning 3-1 win at the Etihad Stadium, but while the Foxes' remarkable season continues to take the spotlight, Spurs' title challenge is gathering pace.
Tottenham have not been so high in the standings with 25 matches played since 2012, when Harry Redknapp's Gareth Bale-inspired team sat third and looked set for a similar tilt at becoming champions.
Spurs, however, then lost their next three games in a row and managed just one win in nine as the team crumbled under the pressure, slipping to fourth and missing out on a Champions League place to Chelsea.
Pochettino's outfit appear to be made of sterner stuff but much will be learned in the next month, with a visit to Manchester City in eight days' time followed by a Europa League double header against Fiorentina and derbies against West Ham and Arsenal.
It was perhaps with those games in mind that Pochettino made four changes to his starting line-up, including dropping Dele Alli to the bench.
Watford, meanwhile, have now won only once in eight matches and this latest defeat means they drop to 10th in the table.
Tottenham dominated the opening 45 minutes but found it difficult to break down the visitors, who were happy to sit deep and soak up the pressure.
The Hornets were determined to channel possession down the crowded centre, while Spurs found joy when moving the ball wide.
One Trippier cross picked out Nacer Chadli but his header was blocked, while Ben Davies twice nipped in behind Allan Nyom but the Welshman's shots were parried away by Gomes.
Tottenham endured one momentary scare when Almen Abdi's long-range effort landed on the roof of the net after Hugo Lloris had rushed out.
However, the best chance of the half came five minutes before the break as Eric Dier chipped a ball forward to Harry Kane and the striker, under pressure, volleyed over from six yards out.
Quique Sanchez Flores introduced Troy Deeney at half-time, presumably to give his side more of an outlet, but Tottenham began the second period with even greater vigour and had two penalty appeals turned down in quick succession.
The first looked the stronger case as Gomes clipped the back of Kane's legs as he moved away from goal, with the striker's header then impeded slightly when Sebastian Prodl slipped and was left floundering on the floor.
With an hour on the clock, Pochettino threw on Alli to initiate the breakthrough and it took the midfielder just four minutes, as he overlapped Mousa Dembele down the left before guiding a cross to the backpost with the outside of his foot for Trippier to slot home.
Tottenham should have put the game to bed in the latter stages as first Lamela went close and then Kevin Wimmer skewed Eriksen's cutback, but it made no difference as the home side held on to keep their title challenge on track.
TWEET OF THE MATCH
Former Spurs midfielder Micky Hazard (@1MickyHazard): "Get in there another win 2nd in the League COME ON BOYS KEEP GOING WE CAN DO THIS COYSSSSSS"
PLAYER RATINGS
Tottenham
Hugo Lloris: 7 (out of 10)
Kieran Trippier: 9
Toby Alderweireld: 7
Kevin Wimmer: 7
Ben Davies: 8
Eric Dier: 7
Mousa Dembele: 7
Erik Lamela: 6
Christian Eriksen: 8
Nacer Chadli: 6
Harry Kane: 7
Substitutes
Dele Alli (for Chadli, 61): 7
Son Heung-min (for Lamela, 72): 7
Tom Carroll (for Eriksenm, 90): 5
Watford
Heurelho Gomes: 7
Allan Nyom: 5
Miguel Britos: 6
Craig Cathcart: 6
Nathan Ake: 7
Mario Suarez: 5
Etienne Capoue: 6
Ben Watson: 5
Jose Manuel Jurado: 5
Almen Abdi: 6
Odion Ighalo: 6
Subs
Valon Behrami (for Suarez, 45): 6
Troy Deeney (for Abdi, 45): 6
Sebastian Prodl (for Britos, 54): 5
STAR PLAYER
Kieran Trippier: Trippier has not been a first-team regular this season but the former Burnley man was handed a starting berth ahead of Kyle Walker and made the most of it with an energetic display down the right, which he capped with a second-half winner and his first goal for the club
MOMENT OF THE MATCH
Delle Alli coming off the bench: Alli was left out of the starting team after feeling dizzy against Norwich in midweek but, with the score 0-0, Pochettino threw on the midfielder on the hour
Within four minutes he had initiated the breakthrough, sliding across a sumptuous pass for Trippier to slot home.
VIEW FROM THE BENCH
Spurs were guilty of spurning a number of decent chances before Trippier finally found the net, but Pochettino was a calm presence on the touchline and he will be delighted to move second in the table with a tricky month of fixtures to come
Watford have now won only once in eight matches and Quique Sanchez Flores' side never looked like ending that run here.
MOAN OF THE MATCH
Why did Troy Deeney start on the bench for Watford? Spurs played three at the back to combat the combative striker and Odion Ighalo in December but with only Ighalo to look after, the home side were able to pour forward with a lot more freedom this time around.
WHO'S UP NEXT
Manchester City v Tottenham (Premier League, Sunday, February 14)
Crystal Palace v Watford (Premier League, Saturday, February 13)
Source : PA
Source: PA