He later received an apology from chairman Bill Kenwright.
Allardyce still has 12 months of an 18-month contract left to run, which reportedly means that the former England boss will receive around £6million in compensation.
The 2017/18 season has now come to a close, and for Everton supporters, it won't be looked back on too fondly despite the club finishing 8th in the Premier League. Allardyce makes a good start, with Everton racking up four wins and three draws from his first seven games in charge to move well away from the relegation zone.
Allardyce took over the reins on November 30 previous year, six months after leaving a similarly short stint at Crystal Palace.
An exasperated Allardyce repeatedly insisted he couldn't have done more than steer them to an eighth-place finish in the Premier League table.
But the style of play under the 63-year-old has not been met with universal appeal among Everton fans.
The Hornets refused to let Silva go only to sack him in January, citing the disruption caused by Everton's "unwarranted approach" for a major dip in form.
GETTY Sam Allardyce could be replaced at Everton by Marco Silva
Allardyce's backroom team of Sammy Lee, Craig Shakespeare and goalkeeping coach Martyn Margetson are also expected to leave Goodison Park as the club undertakes another expensive overhaul of its management structure.
In a statement Everton confirmed Allardyce's departure. However, Watford refused the former Olympiakos boss permission to speak to the Merseysiders. They have since issued a formal complaint to the Premier League, but it is not likely to escalate any further.
Watford "remain furious" that Everton's interest a year ago unsettled Silva and a poor run of form led to his sacking in January.
Silva's Portuguese compatriot Paulo Fonseca, the manager of Shakhtar Donetsk, is second favourite.
"I would like to place on record my honest thanks to David Moyes and his staff for achieving the target of keeping West Ham United in the Premier League", said joint chairman David Sullivan.
Fonseca was another who was linked with the job in November before Allardyce was appointed.
Racing Welfare promotes mental health campaign
The effort is part of a campaign called "Make It OK", and is created to encourage people to talk more openly about mental illnesses and ask for help.