Lagniappe

Lefe had been successful, and was supposed to have amassed quite a "pile," which he was very loth indeed to part with; and when he lost, if the money were not absolutely staked, would usually put off the winner with some old horse that he had fixed up for sale, or a dubious note that he had received as "lanyappe," (Anglice, boot money.)

Source: wiktionary

Lanyap. Something over and above. Louisiana.

Source: wiktionary

We have a custom here among children (and one often sought to be made availing by some of larger growth), that when anything is purchased, a Lagnappe (something thrown in), is expected, and demanded as a right. And since "Jesus died and paid it all, / All the debt we owe." […] may not He claim for His Lagnappe, on the resurrection morn, these living gems [children], who wait "to be clothed upon with their house which is from Heaven?"

Source: wiktionary

We picked up one excellent word – a word worth travelling to New Orleans to get; a nice limber, expressive, handy word – "Lagniappe." They pronounce it lanny-yap. […] It has a restricted meaning, but I think the people spread it out a little when they choose. It is the equivalent of the thirteenth roll in a "baker's dozen." It is something thrown in, gratis, for good measure. […] When a child or a servant buys something in a shop – or even the mayor or governor, for aught I know – he finishes the operation by saying, – 'Give me something for lagniappe.' The shopman always responds; gives the child a bit of liquorice-root; gives the servant a cheap cigar or a spool of thread, gives the governor – I don't know what he gives the governor; support, likely.

Source: wiktionary