The 21-year-old winger was left out of the team that suffered a 2-0 loss to Manchester City on Wednesday, although he was fully fit for the game.
The Portuguese tactician settled for Bernard and Theo Walcott on the flanks witj Richarlison, Cenk Tosun and Gylfi Sigurdsson as his attacking options on the bench.
However, Silva has explained that the absence of the forward was due to ‘technical’ reason and has been listed as part of the squad that will face the Hornets at Vicarage Road.
“He [Ademola Lookman] was fit [against Manchester City],” Silva told Echo. "But he is available for the game [against Watford] and is on the squad list.”
Lookman has made 14 appearances this season for the Goodison Park outfit, involving six starts and scoring once.
Everton are placed ninth in the league log with 33 points from 26 games.