Manager Lee Clark told the club website: "The injury to Anthony [Pilkington] has left us with only one senior winger.
"I like my wide men and Danny brings with him a lot of experience."
Pilkington is out for at least four months after breaking his leg and dislocating his ankle in last week's win over Rochdale, and Ward is seen as a direct replacement.
The Bradford-born winger has made two substitute appearances for Bolton but made his name while on loan at Swindon last season, scoring against Huddersfield in their 2-2 draw.
Everything about the move was right for me - Huddersfield is a good club with a good manager
Danny Ward
"Aidan Chippendale impressed at Bristol Rovers on Saturday [in place of Pilkington] but I feel we need someone with more experience," Clark added.
"We have been monitoring Danny for a while now and have been very impressed with his performances for the Bolton reserve side.
"There were a lot of clubs interested in Danny and I would like to thank Owen Coyle for letting us have him until the end of the season."
Ward, who scored nine goals in 32 appearances while at Swindon, said: "I know quite a lot about the club - I am from Bradford, so I have seen their progress.
"They did really well last year and were unlucky not to gain promotion.
"Everything about the move was right for me, Huddersfield is a good club with a good manager.
"I feel my natural position is on the left wing; I like to get on the ball and put it into the box for the strikers to attack.
"I can't wait to start playing first-team football again. Hopefully while I am here I will be able to help the club achieve promotion."
Source: BBC Sport
Source: BBC Sport