The Belgium international tapped home Ramiro Funes Mori's low cross after 63 minutes of the meeting at Villa Park, with the Toffees already two in front and cruising against Remi Garde's struggling side.
And it proved to be a significant strike for Lukaku, who has now scored more goals than any other Everton player in a single Premier League season as he netted his 17th of the campaign.
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Tony Cottee (in 1993-94) and Andrei Kanchelskis (in 1995-96) had previously held the record, with Lukaku's strike against Villa taking him above Harry Kane and into second in the race for the golden boot.
The goal also saw the former Chelsea striker equal his own personal best, with Lukaku having netted 17 Premier League goals during a loan spell with West Brom back in 2012-13.