Definition of vicinal
1 : of or relating to a limited district : local
2 : of, relating to, or substituted in adjacent sites in a molecule <a vicinal disulfide group>
Origin and Etymology of vicinal
Latin vicinalis, from vicinus neighbor, from vicinus, adjective, neighboring
First Known Use: circa 1623
Seen and Heard
What made you want to look up vicinal? Please tell us where you read or heard it (including the quote, if possible).