Use 'witless' to express criticism or an negative opinion about someone's intellect. His witless behavior during the meeting suggested he hadn't prepared at all.
Pro Tip 2/3
Emotional Impact
The word 'witless' can be hurtful or offensive; use it cautiously to avoid insulting someone. Calling someone witless in an argument can escalate the situation.
Pro Tip 3/3
Informal Situations
'Witless' is more common in informal language and can seem too harsh in formal contexts. At a friendly roast, someone might jokingly say, 'You are completely witless!'