(1) By means of, by way of.  From Latin for "way" or "path."
(2) (
Virtual 
Interface 
Architecture)  See 
VI.
(3) For Intel's chip power and interconnect separation architecture, see 
PowerVia.
(4) (
Vertical 
Interconnect 
Access)  In a printed circuit board, a conducting pathway between layers.  The via is created by drilling a hole through the board where the layers interconnect.  Copper fills the hole entirely or coats only the sides of the hole.  See 
printed circuit board.
(5) (
Vertical 
Interconnect 
Access)  In a 3D chip, a conducting pathway between layers.  Two or more stacked die are connected by "through-silicon vias" (TSVs), which are pathways that pass completely through the die.
TSV Pathways Between 3D Chips
The vertical blue lines are the insulated through-silicon vias (TSVs) between two chips on the same package.  See 
system in package.
 
Creating Vias on Programmable Chips
In the antifuse programmable chip technology, a circuit is closed by turning non-conductive silicon into a conductive via.  See 
antifuse.