The former Bolton forward capped an influential first-half show with two long-range strikes after the break before being substituted.
He cut inside on 65 minutes from Oliver Norwood's pass down the right flank and lashed a 20-yard rising drive into the roof of the net.
That made it 4-1 to the home side and just three minutes later Norwood created another opening for Ward, who again blasted home from 25 yards.
This time keeper Chris Dunn, who replaced Marek Stech at half-time, saved the effort only to let the ball slip through his hands.
Ward, who created two goals in the first half, was given a standing ovation by home fans when substituted on 69 minutes.
Huddersfield trailed on 14 minutes when Yeovil's Ishmael Miller fired in from close range after Town failed to clear a corner.
The ball was turned back into the box and headed on by Liam Davis for on loan Nottingham Forest striker Miller to finish with a drilled shot.
Second-bottom Yeovil, seeking only a fifth league win, looked comfortable despite the Terriers dominating possession.
The Glovers could have been in front even earlier when home keeper Alex Smithies made a mess of an attempted clearance.
He kicked straight to Miller under pressure from James Hayter on 10 minutes, with the forward only denied by a goal-saving block from Joel Lynch.
But Town, prompted by midfielder Hogg and the influential Ward, stepped up a gear to lead 3-1 at the break.
Hogg put Ward in down the left on 23 minutes and the Bradford-born winger crossed for Adam Clayton to tap home from close range.
Ward next helped put Town in front by latching on to a powerful headed clearance from defender Murray Wallace on 40 minutes.
He scampered to the byline and crossed for the unmarked Martin Paterson, who smashed a rising drive into the net at the far post.
Huddersfield were 3-1 up just three minutes later when Lynch squeezed a header in at the near post from Adam Hammill's corner from the left.
Yeovil, hit when Ed Upson had to go off in the first half with an injury, came out strongly after the break.
Upson's replacement Joe Ralls tested Smithies from distance on 56 minutes and the keeper then denied Davis three minutes later.
But in a mirror of the first half Huddersfield moved up a gear to equal their biggest win of the season.
They could have gone one better than the 5-1 thrashing of Bournemouth in August late on when Hammill had a goal-bound shot blocked by a defender.