Hi Camilo, I don't think there is a single way to translate the word "colmo" into English. There are just too many nuances to the word in Spanish, and I think it will very much depend on the specific context of the sentence. In your specific example, I think a valid translation would be "ultimate irony", such as "the ultimate irony for a taxi driver would be that he be named Uber"

Rigel has given you a great translation for your specific joke. If you are looking for ways to translate "colmo" in other contexts, for example in a sentence where the Spanish expression "para colmo" would be a natural choice, some English expressions you could use are "to top it all", "to cap it all", "to crown it all". To use your joke as a reference point - let's say you're telling a story about a specific taxi experience of yours - then you might want to end it with a punch line like "To top it all, the taxi driver's name was Uber." Another expression, "para colmo de desgracias", could be translated as "to make matters worse". And if you would like to find more options, look up the word "colmo" on SpanishDict.com. There you'll find some great examples of various ways to translate a selection of "colmo"-expressions :)