Forgetting to turn off your turn signal after making a turn, thus annoying drivers behind you for several miles-- because of the chain reaction and having to slow down so they don't rear-end the car ahead. Also can happen when you accidentally bump the turn signal while reaching for something on the dashboard. Example: Dad, you've got blinker cluelessness _again_.
BLINKER CLUELESSNESS
Meaning of BLINKER CLUELESSNESS in English
Slang English vocab. Английский сленговый словарь. 2012