Noun
pin joining a piston to a connecting rod
Source: WordNetA characteristic of most trunk pistons, particularly for diesel engines, is that they have a groove for an oil ring below the gudgeon pin, in addition to the rings between the gudgeon pin and crown. Source: Internet
To make these more compact, they avoided the steam engine's usual piston rod with separate crosshead and were instead the first engine design to place the gudgeon pin directly within the piston. Source: Internet
The sides of the piston skirt around the gudgeon pin are reduced away from the cylinder wall. Source: Internet
Three compression and one oil-control ring above the gudgeon pin, and one oil-control ring below. Source: Internet