Two quickfire first-half goals, separated by 144 seconds, set Spurs on their way.
Victor Wanyama scored his first of the season on 24 minutes after rounding Ben Hamer.
Lucas doubled Spurs’ advantage by powering in Moussa Sissoko’s pass from the right.
After Huddersfield had briefly threatened late on, with Juninho Bacuna's free-kick hitting the woodwork, Lucas struck twice in the final five minutes.
He first skilfully converted Christian Eriksen’s cross before finishing off substitute Son Heung-min’s through-ball, celebrating after the match with his one-year-old son.
Huddersfield remain bottom with 14 points.