Lavery has only played twice for Wednesday this season, and that simply wasn't enough to keep the forward satisfied.
As a result, he has gone out on loan, and the 22-year-old says he is looking forward to getting started at Portsmouth, after agreeing to a three-month temporary move," he said.
"I’d like to be part of the success that I’m sure Pompey will have this season and I’m looking forward to getting started.
"At the age I’m at now, I need to be playing games on a regular basis and scoring goals."
Lavery scored goals at Championship and League One level last season, so there are high hopes for the impact he could make at Fratton Park.
Portsmouth are one of the strongest teams in League Two, and they currently sit second in the table, meaning Lavery should be part of a promotion push.
During his time with Portsmouth, Lavery will be competing with the likes of Matt Tubbs, Adam McGurk and Conor Chaplin for a place up-front, but he should get greater chances than at Wednesday.
Carlos Carvalhal has tended to pick other options ahead of Lavery this season, with Lucas Joao and Atdhe Nuhiu ahead of him in the pecking order.