Ireland: The A-Z Irish Glossary - 'N' is for 'Nixer'
'Nixer'
An unofficial one-off job done without the knowledge of the Revenue Commissioners (Tax Office) where the worker gets paid cash into their hand.
Example: "Jim's
company wanted a website so I did a nixer for them at
the weekend".
A nixer is generally an old method of work and was a way for people to use their skills and get paid during a recessionary period where they could not find official employment.
Also, often a nixer is done for payment in kind rather than for cash.
A bottle of whisky is common reimbursement.