lamencourt
When someone says they will meet u somewhere and then bails do too pending snowstorm that never happens.
Dave pulled a lamencourt when failing to meet his friends.
Lamencourt
(n) A person who ditches plans with his friends for unacceptable reasons.
Dave was a total Lamencourt when he wouldn't meet up at the bar because he "had to baby-sit" and "it might snow half an inch."