1. What does it mean?
존버 is a coarse contraction commonly understood as 존나 버티다. It means enduring a difficult situation or refusing to give up, and in investing it often means continuing to hold an asset despite a loss.
Also written or said as jonbeo
2. The nuance
The underlying intensifier is vulgar. Persistence does not guarantee success or a financial recovery; this entry explains the slang, not a recommendation to keep a position.
3. Examples
“세일을 기다리며 존버했는데 결국 안 샀어.”
I stubbornly waited for a sale but ended up not buying it.
“존버하면 무조건 오른다는 말은 믿지 않아.”
I don't believe the claim that holding on always guarantees a price rise.
Sources
References support the meaning and usage. Example sentences are written for NoCapWiki.