To be slightly depressed and incredibly lethargic. Extreme pessimism. A loss of desire to do anything. Can cry at any moment.
When Aiden failed four classes and swam slow in his swim meet he felt tabbed out.
When Aiden decided to wear a hand-me down sweater and hang Christmas lights in July, his extreme tabbness was displayed.
It was obvious that Aiden was tabbed when he continuously replayed a specific Simon and Garfunkle song and hadn't showered in 11 days.