a pressure/massage point
- something that exactly matches one’s taste
- something that makes you laugh a lot
- a level of humour that makes you laugh
壺 (つぼ) is a homophone which means “a pot”.
ツボ originally means “a pressure/massage point”: a point that stimulates your body very much. Therefore, it figuratively describes something or someone that stimulates you in a “pinpoint” manner and that exactly matches your taste. It’s usually used as ツボにハマる (or ツボる in short), meaning “(something) exactly matches one’s taste”.
When it’s used in the context of humour, it means something that matches your sense of humour and makes you burst into laughter, as if it pushing your “pressure point” for laughing. In this context, ツボにハマる (or ツボる) means “to burst into laughter” or “cannot stop laughing”. Interestingly, ツボ also means your “laughter threshold”: a level of humour that makes you laugh, e.g. ツボが浅い (tsubo is shallow) indicates people who easily laugh (even at cheesy jokes). Such people are called ゲラ, which comes from ゲラゲラ, an onomatopoeia for laughing loud.
His singing voice exactly matches my taste.
My friends often tell me that I laugh at weird things.
The level of humour that she finds funny is very low, and she laughs very easily.