The 21-year-old striker has already been at Huddersfield this season with their development squad and scored goals in the Under-21 victories over Barnsley and Sheffield United in December.
"We were pleased with what we saw of Harry and he did well in a short space of time," Terriers manager Mark Robins told the club's official website. "He fitted in well with the group and caught the eye in his performances for the Under-21s.
"Although our first team supporters didn't get the chance to see him, the loan period proved to be extremely worthwhile for us. We believe Harry can develop further and we'll work hard with him on the training ground to aid that development."
Huddersfield are 13th in the Championship, seven points off the top six.