Suffering from loss of facial utility, typically characterised by inability to outwardly exhibit emotion.

Linked to overuse or abuse at the hands of a particularly menial task.

See rackface.
Alice: Since his stint on the last project, Richard's been suffering from a disctinct case of slackface.

Bob: I know; I heard that project was a biatch.
by outofcoffee October 8, 2008
Get the slackface mug.
The expression of a mentally deficient person as they stumble through a realm of consciousness unknown to that of people with the proper number of chromosomes.
Look at that slackfaced motherfucker trying to hump a doorknob!
by Slackfaced June 2, 2018
Get the Slackface mug.