The paperwork was processed in time for the 6ft 4in 22-year-old to make his debut against Birmingham City on Tuesday evening in the Carling Cup.
McAliskey was on the bench against Mansfield Town in the first round of the competition, but because he did not enter the action he is not cup-tied.
The Terriers loaned McAliskey to Torquay for two months last season.
BBC