"He has a long way to go," Belichick said of the defensive back, whose signing was announced Saturday. Terms of the deal were no disclosed.
Meriweather, the 24th overall pick, had 91 tackles for the University of Miami last season, his senior year. His best statistical season came the year before, when he had 115 tackles. The 5-foot-11, 200 pound Meriweather finished his college career with seven interceptions.
Meriweather, 23, was New England's only unsigned draft choice. During drills, he stayed with Moss, who caught two passes from Tom Brady on short sideline routes.
Belichick said Meriweather would workout at cornerback and safety.
"He's played a lot of different positions in college," Belichick said. "People on our team are going to have to have some versatility and play different spots anyway, so he falls into that category."
The team did not make Meriweather available to the media.
His signing comes as cornerback Asante Samuel's holdout continued into the second day of training camp. Samuel is holding out for a multiyear agreement after rejecting a one-year, $7.79 million contract.