A small amount; a little bit.
"The school counselor advised students to avoid any activities involving tad before returning to class."
Initialism of tobacco, alcohol and drugs.
simple past tense and past participle of TA
"I put a tad more sugar in my coffee, but it still tasted too sweet to me."
A diminutive of the male given name Thaddeus or Thaddaeus.
"The new employee introduced himself as Tad to everyone at the office, though his full name is actually Thaddeus."