Wordnet 3.0
NOUN (1)
1.
a small gift (especially one given by a merchant to a customer who makes a purchase);
The Collaborative International Dictionary of English v.0.48:
Lagniappe \La*gniappe\, Lagnappe \La*gnappe"\, n. [Also spelled
lagnappe.][Etym. uncertain.]
1. In Louisiana, a trifling present given to customers by
tradesmen; a gratuity.
[1913 Webster]
Lagniappe . . .is something thrown in, gratis, for
good measure. --Mark Twain.
[Webster 1913 Suppl.]
2. A tip or gratuity.
[PJC]
3. Hence: Anything obtained gratuitously or unexpectedly.
[PJC]
WordNet (r) 3.0 (2006):
lagniappe
n 1: a small gift (especially one given by a merchant to a
customer who makes a purchase)