It was the 10th time in a row that Root has failed to convert a Test fifty into a century and his dismissal ended England's realistic hopes of winning the match.
England failed to make the positive start they wanted following their heavy Ashes defeat in Australia and a rare series loss in New Zealand.
England, resuming Sunday on 235 for six in their second innings, lost their last four wickets for just seven runs in 18 balls to be bowled out for 242. "We were outperformed in all three departments".
"Pakistan's bowlers exploited the conditions well but we played some poor shots and you can't afford to do that".
"But we had that belief that he will come good. Our bowlers did a great job for us".
Root said he had no regrets about opting to bat first.
Amir, whose career nearly came to a complete end at Lord's back in 2010 after he received a jail sentence and five-year ban from cricket for his involvement in a spot-fixing scandal during a corresponding Test against England, had taken two wickets for no runs in three balls.
"It would be very easy going into next week feeling sorry for ourselves and thinking that there is no way forward, but there absolutely is", said 27-year-old Root.
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Après une courte réflexion, il choisit doit choisir celui qu'il affrontera lors du dernier Conseil, et il désigne Clémence . Pour plusieurs d'entre eux, le candidat a mené une belle aventure et aurait mérité la place de vainqueur.
Meanwhile the recalled Hasan, who did not play in Pakistan's win over Test debutants Ireland in Dublin concluded last week, took four for 51 in 15.2 overs.
Before the start of this match, most people assumed that this Pakistan challenge would be gobbled up with relatively ease, instead England have managed to choke on it and then spit it all over their pants. It was they who made the most of the bowling conditions to skittle England for a modest first innings score, they who refused to succumb to the panic of yet another batting collapse every time they lost a key wicket and they who produced an all round team performance to comfortably outplay underprepared-looking opponents.
England´s were now 236 for seven and that soon became 241 for eight, after the tourists took the new ball, when Mark Wood edged Mohammad Amir to Pakistan captain and wicket-keeper Sarfraz Ahmed.
This is Pakistan fifth Test victory at Lord's following wins at the "home of cricket" in 1982, 1992, 1996 and 2016.
And on Sunday he fell for a duck when prodding Abbas to Sarfraz.
And Amir put England out of their misery in emphatic fashion by crashing a full delivery into the off stump of Bess (57), before Imam and Sohail briskly took care of business prior to lunch.
As Mohammad Amir (four for 36) and Mohammad Abbas (four for 41) shared the spoils, and Pakistan were set only 64 for victory, Joe Root's team extended their winter woes on to home territory - losing their sixth...