Lavery has made three substitute appearances for Wednesday this season, the last of those coming against Barnsley last month.
The 21-year-old, who had a spell with Southend earlier this year, could make his Pilgrims debut against Dagenham & Redbridge on Saturday.
"I've watched him a few times and I've had really good reports on him," Sheridan told the club's official website.
"He scores goals at reserve-team level so hopefully he will come in here, try to get a few starts and get a few goals for us. He's really keen to come and play. I'm very pleased to get him."
- Sports & Recreation