The 31-year-old forward has mostly appeared as a substitute in the opening 10 league fixtures, with his only start coming in the 3-0 home defeat to West Ham.
Summer signing Roberto Soldado has been preferred by Villas-Boas and Defoe has mostly been called upon for Europa League fixtures.
Defoe became Tottenham's all-time leading goalscorer in European competitions with his converted penalty in Thursday's 2-1 win over Sheriff Tiraspol.
With a World Cup coming at the end of the season Defoe will be keen to feature more in the coming months, but Villas-Boas has insisted he will be going nowhere during the winter transfer window.
When asked if Defoe could leave White Hart Lane, the Portuguese manager replied: "No, I don't think so.
"We are pretty happy with the goals he is producing. He is on nine goals already so it is a great start for him and it doesn't change our perspective regarding his position in the team.
"I'm not sure about the selection process for [England manager] Roy Hodgson but from what I have seen he has been counting on Jermain in the same way and he has been included in all call-ups since we started playing this season."
Villas-Boas said he has been pleased with the contribution of both Defoe and Soldado, who have scored 15 goals between them across all competitions.
"We've been rotating," Villas-Boas said.
"What has been happening is we have given opportunities for players who have played in the Europa League to break into the Premier League team.
"A couple of them have received a vote of confidence to continue to play and Jermain played in the game against West Ham and then we went back to Soldado playing in the Premier League.
"I'm extremely happy with both, it is just a question of deciding what is better on a specific date and regarding specific strategies.
"Obviously everyone wants to play consecutively and get matches in the Premier League.
"But we have found comfort playing in this system and we have three strikers competing for that position and it hasn't been easy for any of them."