1. In a manner that lacks sensitivity, diplomacy, or consideration for others' feelings
She tactlessly mentioned his weight gain at the dinner party.
Ela mencionou sem tato o ganho de peso dele na festa de jantar.
2. In an insensitive or impolite way; rudely or bluntly
He tactlessly criticized her presentation in front of everyone.
Ele criticou sua apresentação sem tato na frente de todos.