" demob "

 [ "demob" ]

1: Demob is shortning of a military term for the demobilisation of military forces, came about in in 1945 when the british armed forces were sent back to blighty and therfore extreamly happy.

  * e.g.,  ... It's my last day of work before my 2 week holiday and I am Demob happy. 

 [ "demob suit" ]

1: at the end of the Second World War, returning servicemen underwent a 'demobilisation' process at various centres around the country. As part of this process of transitioning back into civilian life, they were issued with an outfit of civilian clothing. This included a new suit, which became known as a 'demob' (short for demobilisation) suit. Accordingly, the phrase has become synonymous with any suit that looks sufficiently mass-produced and out of style that no-one in their right mind would buy it themselves.

  * e.g.,  ... He goes to so few formal occassions, the last time he did he was wearing his demob suit.