The Frenchman struck with a 65th-minute header to seal a tight encounter which never really took off, although the Gunners were grateful when goalkeeper Wojciech Szczesny blasted a clearance straight at Loic Remy and saw the ball run just wide of the post with time running down.
Arsene Wenger's men enjoyed long periods of possession at St James' Park, but were rarely able to make it count, and it took a set-piece from Theo Walcott, who was otherwise largely anonymous, to present Giroud with his big chance.
Newcastle might have gone in ahead at the break had Szczesny not tipped over Moussa Sissoko's effort or had Mathieu Debuchy's header not come back off the crossbar.
However, they were unable to sustain the pressure as they slipped to just a second defeat in 10 league outings in front of a crowd of 52,161.
Chelsea claimed a 2-1 win over Liverpool in a pulsating Barclays Premier League clash at Stamford Bridge.
In Luis Suarez's first match with Chelsea since April's infamous bite on Branislav Ivanovic earned him a 10-match ban, Jose Mourinho's side deprived the prolific striker of scoring opportunities and took full advantage.
The Blues responded from going behind to Martin Skrtel's fourth-minute goal with a brilliant Eden Hazard effort and a rare striker's goal.
Samuel Eto'o showed a goal-poacher's instinct to decide the game with his third Premier League goal of the season - and just the sixth by a Chelsea striker.
Liverpool hit the bar through Mamadou Sakho and might have had a penalty when John Terry clumsily clambered over Suarez in the box; although Hazard also had justifiable claims for a first-half spot-kick dismissed by referee Howard Webb.
Suarez had another penalty claim denied when Eto'o tripped him off the ball as Chelsea held on to move two points behind leaders Arsenal in third place.
Liverpool are six points off the pace at the halfway stage of the season.
Everton finished 2013 on a high as Romelu Lukaku's first goal in six games helped them to a 2-1 home victory over Southampton.
The Toffees - looking to bounce back from the Boxing Day defeat to Sunderland that had ended their hopes of going through the whole calendar year unbeaten at Goodison Park in the league - went ahead in the ninth minute when Seamus Coleman burst into the area and finished with a powerful strike.
Saints substitute Gaston Ramirez equalised in the 71st minute, beating Toffees goalkeeper Joel Robles, who it appeared should have done better in his attempt to save the effort, with a shot from distance.
But the hosts were back in front as Lukaku converted from James McCarthy's pass, the on-loan Chelsea striker taking his tally for Everton this season to nine goals.
Tim Sherwood tasted victory at White Hart Lane for the first time as Tottenham put on a vintage display to defeat Stoke 3-0.
Roberto Soldado converted his fifth penalty of the campaign while Aaron Lennon and Mousa Dembele also scored fine goals to give Spurs a comfortable win.
Dembele and the returning Paulinho bossed the midfield against a physical Stoke side while Lennon's performance on the right flank gave Tottenham extra cutting edge.
NEWCASTLE UNITED 2013/14
PREMIER LEAGUE
NEWCASTLE 0 ARSENAL 1
Krul, Debuchy, Williamson, Coloccini, Santon, Anita (74' Shola Ameobi), Tiote, Sissoko (79' Haidara), Cabaye, Gouffran (62' Ben Arfa), Remy
Subs: Cisse, Yanga-Mbiwa, Elliot, Sammy Ameobi
NEWCASTLE 5 STOKE CITY 1 (Remy 2, Gouffran, Cabaye, Cisse pen)
Krul, Debuchy, Williamson, Coloccini, Santon (61' Haidara), Anita (45' Shola Ameobi), Sissoko, Ben Arfa, Cabaye, Gouffran (72' Cisse), Remy
Subs: Yanga-Mbiwa, Elliot, Obertan, S Taylor
CRYSTAL PALACE 0 NEWCASTLE 3 (Cabaye, Gabbidon og, Ben Arfa pen)
Krul, Debuchy, Williamson, Coloccini, Santon, Anita, Tiote, Sissoko, Cabaye (79' Ben Arfa), Gouffran, Remy (75' Shola Ameobi).
Subs: Cisse, Yanga-Mbiwa, Haidara, Elliot, Obertan
NEWCASTLE 1 SOUTHAMPTON 1 (Gouffran)
Krul, Debuchy, Williamson, Coloccini, Santon (78' Haidara), Sissoko, Anita, Tiote, Gouffran (73' Ben Arfa), Shola Ameobi (61' Cisse), Remy
Subs: Yanga-Mbiwa, Elliot, Obertan, Sammy Ameobi
MAN UTD 0 NEWCASTLE 1 (Cabaye)
Krul, Debuchy (83' Yanga-Mbiwa), Williamson, Coloccini, Santon, Cabaye (78' Shola Ameobi), Tiote, Anita, Sissoko, Remy, Gouffran (57' Ben Arfa).
Subs: Cisse, Gutierrez, Elliot, Obertan
SWANSEA 3 NEWCASTLE 0
Krul, Debuchy, Williamson (77' Yanga-Mbiwa), Coloccini, Santon (56' Haidara), Sissoko, Tiote, Cabaye, Gouffran, Shola Ameobi (67' Obertan), Remy
Subs: Anita, Elliot, Sammy Ameobi, Dummett
NEWCASTLE 2 WBA 1 (Gouffran, Sissoko)
Krul, Debuchy, Williamson, Coloccini, Santon, Sissoko (90+5' Cisse), Tiote, Cabaye, Gouffran, Shola Ameobi, Remy (84' Anita)
Subs: Ben Arfa, Yanga-Mbiwa, Elliot, Obertan, Sammy Ameobi
NEWCASTLE 2 NORWICH CITY 1 (Remy, Gouffran)
Krul, Yanga-Mbiwa, Williamson, Coloccini, Santon, Sissoko, Tiote, Cabaye (68' Anita), Gouffran (83' Ben Arfa), Shola Ameobi (74' Cisse), Remy.
Subs: Haidara, Elliot, Obertan, Sammy Ameobi
TOTTENHAM 0 NEWCASTLE UTD 1 (Remy)
Krul, Debuchy, Williamson, Yanga-Mbiwa, Santon, Sissoko, Cabaye, Tiote, Gouffran (85' Obertan), Remy (75' Cisse), Shola Ameobi (60' Anita).
Subs: Coloccini, Ben Arfa, Elliot, Sammy Ameobi
NEWCASTLE UTD 2 CHELSEA 0 (Gouffran, Remy)
Krul, Debuchy, Williamson, Yanga-Mbiwa, Santon, Sissoko, Cabaye, Tiote (53' Anita), Gouffran (85' Obertan), Shola Ameobi (62' Cisse).
Subs: Ben Arfa, Elliot, Sammy Ameobi, Tavernier.
SUNDERLAND 2 NEWCASTLE 1 (Debuchy)
Krul, Debuchy, Williamson, Dummett, Santon, Sissoko (45' Cisse), Tiote, Cabaye, Gouffran (86' Sammy Ameobi), Ben Arfa, Remy (70' Shola Ameobi).
Subs: Anita, Haidara, Elliot, Obertan.
NEWCASTLE UTD 2 LIVERPOOL 2 (Cabaye, Dummett)
Krul, Debuchy, Williamson, Yanga-Mbiwa, Santon, Cabaye (78' Sammy Ameobi), Tiote, Gouffran, Sissoko (45' Dummett), Remy, Ben Arfa (78' Anita).
Subs: Cisse, Elliot, Obertan, Dummett.
CARDIFF CITY 1 NEWCASTLE 2 (Remy 2)
Krul, Debuchy, Williamson, Coloccini, Santon, Tiote, Cabaye (86' Ben Arfa), Gouffran, Sissoko, Remy (71' Gutierrez), Cisse
Subs: Anita, Yanga-Mbiwa, Elliot, Sammy Ameobi, Dummett
EVERTON 3 NEWCASTLE 2 (Cabaye, Remy)
Krul, Debuchy, Yanga-Mbiwa (46' Williamson), Coloccini, Santon, Tiote, Anita (69' Cisse), Ben Arfa (46' Cabaye), Sissoko, Gouffran, Remy
Subs: Elliot, Obertan, Sammy Ameobi, Dummett
NEWCASTLE 2 HULL CITY 3 (Remy 2)
Krul, Debuchy (86' Tiote), Yanga-Mbiwa, Coloccini, Santon, Cabaye (62' Gouffran), Anita, Sissoko, Ben Arfa, Cisse (73' Marveaux), Remy
Subs: Williamson, Elliot, Sammy Ameobi, Dummett
ASTON VILLA 1 NEWCASTLE 2 (Ben Arfra, Gouffran)
Krul, Debuchy, Coloccini, Yanga-Mbiwa, Santon, Anita (74' Tiote), Cabaye (88' Sammy Ameobi), Ben Arfa, Sissoko, Remy (63' Gouffran), Cisse
Subs: Elliot, Marveaux, S Taylor, Dummett
NEWCASTLE 1 FULHAM 0 (Ben Arfa)
Krul, Debuchy, Yanga-Mbiwa, Coloccini, Santon, Ben Arfa, Sissoko, Anita 65' (Cabaye), Marveaux 74' (Remy), Shola Ameobi 65' (Gouffran), Cisse
Subs: Gosling, Elliot, Sammy Ameobi, Dummett
NEWCASTLE 0 WEST HAM 0
Krul, Debuchy, Yanga-Mbiwa, Coloccini, Santon, Ben Arfa, Sissoko, Anita, Marveaux 66' (Sammy Ameobi), Shola Ameobi, Cisse 72'
Subs: Gosling, Bigirimana, Elliot, Vuckic, Dummett
MAN CITY 4 NEWCASTLE 0
Krul, Debuchy, Coloccini, S Taylor, Yanga-Mbiwa, Sissoko, Tiote, Gouffran 45+4' (Dummett), Ben Arfa 65' (Sammy Ameobi), Gutierrez 44' (Anita), Cisse
Subs: Elliot, Marveaux, Shola Ameobi, Obertan
LEAGUE CUP
NEWCASTLE 0 MAN CITY 2 (AET)
Krul, Debuchy, Williamson, Yanga-Mbiwa, Haidara (45 Dummett, 80 Ben Arfa), Anita, Tiote, Gouffran, Sissoko, Shola Ameobi (66 Cabaye), Cisse
Subs: Remy, Elliot, Obertan, Sammy Ameobi
NEWCASTLE 2 LEEDS UTD 0 (Cisse, Gouffran)
Krul, Debuchy, Williamson, Coloccini, Dummett, Gouffran (90' Vuckic), Anita (80' Gosling), Tiote, Marveaux, Sammy Ameobi, Cisse (71' Obertan).
Subs: Ben Arfa, Yanga-Mbiwa, Bigirimana, Alnwick
MORECAMBE 0 NEWCASTLE 2 (Shola Ameobi, Sammy Ameobi)
Elliot, Debuchy, Yanga-Mbiwa, Good, Dummett, Bigirimana, Gosling, Marveaux 88' (Sissoko), Vuckic 46' (Shola Ameobi), Sammy Ameobi, Gouffran 71' (Ben Arfa)
Subs: Santon, Anita, Alnwick, Streete