All 3 Uses

tact
in
The Witch of Blackbird Pond
(Auto-generated)

Kit stared, too aghast to realize her own tactlessness.†
p. 52.6 *

tactlessness = to say or handle things in a needlessly offensive way

standard suffix: The suffix "-lessness" in tactlessness means in a state without. This is the same pattern you see in words like fearlessness, powerlessness, and harmlessness.
With a startled glance up the road, John tactfully freed himself.†
p. 139.6

tactfully = in a manner that makes others feel good
Kit was too astonished to be tactful.†
p. 176.2

tactful = to say or handle things in a way that makes others feel good about them

Definitions:

(1) (tact)
the ability or act of saying or handling things in such a way that others feel good about them
(2) (meaning too rare to warrant focus)