— thanklessly , adv. — thanklessness , n.
/thangk"lis/ , adj.
1. not likely to be appreciated or rewarded; unappreciated: a thankless job.
2. not feeling or expressing gratitude or appreciation; ungrateful: a thankless child.
[ 1530-40; THANK + -LESS ]
Syn. 1. unacknowledged, vain, unrewarding, profitless.