Smithies, credited with three "world class" stops in the 1-1 draw with Bournemouth last week, denied Eoin Doyle on 29 minutes with a wonder save.
Doyle headed a Matthew Kennedy cross from the right to where Smithies had just moved from.
But the Town keeper adjusted his body in mid-air to tip over for a corner a header which looked destined for the net.
Cardiff, who have now drawn four matches in a row, had the better chances in a dour struggle.
Craig Noone's ball into the box from an Aron Gunnarsson long throw on 35 minutes saw Sean Morrison head over unmarked.
Huddersfield's Tommy Smith, making his 50th league appearance for Town, was lucky not to be sent off in first half stoppage time for a foul on Kenwyne Jones.
Smith, who was booked, appeared to be the last man when he brought Jones down on the edge of the box.
A Huddersfield attack broke down and Cardiff swept forward on the break, with Doyle crossing for Jones only for Smith to take him out.
The resulting free-kick by Peter Whittingham flicked off a defender for a corner which came to nothing.
At the other end former Cardiff skipper Mark Hudson headed over a Jacob Butterfield corner early on.
Centre back Morrison, a Huddersfield play-off final penalty hero in 2012, and Bruno Ecuele Manga dominated in the air.
James Vaughan, who had scored in his last three games and hit five goals in 10 matches since returning from injury, was kept quiet.
It was his strike partner Nahki Wells who had a chance but Cardiff goalkeeper David Marshall smothered at his feet.
Butterfield also looked to put Jack Robinson through, but he was crowded out in the box.
Just after the restart Whittingham was denied a goal when Kennedy found him alone near the penalty spot with a low cross.
The midfielder's shot was blocked by Hudson, who rapidly closed the gap down to keep the scores level.
Huddersfield went close through shots from Butterfield and Smith on 53 and 58 minutes while Wells had a header saved on 65 minutes.
Whittingham had another shot blocked soon after and then Noone blasted from about 25 yards on 78 minutes.
Cardiff, seeking only a second away win all season, soaked up Town pressure late on and hit on the break.
Crosses from Doyle and Noone were hacked clear, with a timely intervention from Murray Wallace denying Jones.
A shot from Noone was also charged down on 89 minutes as Huddersfield battled to avoid a third consecutive home defeat for the first time in 15 years.