1. A thin layer of material, typically wood, applied to a surface to give it a different appearance. This is the most common usage. Examples:
* "The table had a beautiful mahogany veneer."
* "He tried to put on a veneer of sophistication." (metaphorical, meaning he pretended to be more sophisticated than he was)
2. A superficial or artificial appearance that conceals the true nature of something. This definition is more metaphorical. Examples:
* "His charm was just a veneer, hiding his true self."
* "The peace treaty was just a veneer over a simmering conflict."
In both definitions, the key idea is that veneer is a thin covering that hides what lies underneath.