The highly-rated striker has joined the Pilgrims for an initial 28-day period.
Chadwick (22) has previous loan experience at Gainsborough Trinity, FC Halifax Town and Irish side Linfield, where he played and scored in the Europa Conference League.
He will wear squad number 20 at the Jakemans Community Stadium – vacated by the return of Jean Leroy Belehouan to Sheffield United.
Belehouan scored once in 16 appearances – but has not played since November 8 due to concussion protocols. He returns to Bramall Lane with the club's best wishes for the future.