Of or pertaining to a neighborhood; neighboring. / (chemistry) Describing identical atoms or groups attached to nearby (especially adjacent) atoms in a molecule.

(rare) adjacency / (chemistry) The presence of vicinal substituents in a molecule

In a vicinal manner

proximity; the state of being near. / neighbourhood; nearby region; surrounding area. / approximate size or amount.

(organic chemistry) An alkaloid extracted from the seeds of the vetch (Vicia sativa) as a white crystalline substance.

(obsolete) Nearby; neighbouring; vicinal.

plural of vicinity

(organic chemistry) Any diol in which the two hydroxy functional groups are attached to adjacent carbon atoms.

plural of vicinal diol