ZsA cursory look at ancestry shows most having that name are English or American. It doesn't translate to anything in a modern language, as far as I know. I did find something interesting though, Joao Pimentel Eacho, born in Portugal, recorded as going to Rhode Island during the 19th century. There was also a 'Joad Eacho' travelling alongside a Manuel and an Antonio Coelho. Joad- although not a popular name- has wide historic roots, being found across the Anglo world, but also in Latin America and, more frequently, Brazil. Both Manuel and Antonio could be Spanish or Portuguese (or other), but Coelho is specifically a Portuguese surname. Having this combination of people when emigrating makes me suspect that this Joad Eacho has Portuguese roots, and therefore that Eacho is of Spanish/Castilian or Portuguese origin. With Joao Eacho above being Portuguese, it's possible therefore that Eacho has Portuguese roots, but that is not definite at all and is based on very loose evidence unfortunately.

However, first names tell a different possible story. One Eacho was called Eva Fuentes Eacho. Fuentes is a Spanish surname, specifically. Of course, this is just one person, there's another named Olaf Eacho and I'm not saying it's Norwegian. Most likely, it's from Spain or Portugal, however, but which area, or which one, is difficult to say. There's later a Herma Gomez Eacho. Gomez is a Spanish surname, Gomes is Portuguese. Again, this could just be a simple writing and recording error, it's difficult to say. On the basis of first names, most evidence points towards Spain, but on the basis of actual point of departure lists, it's Portugal, with João's name also pointing to this, with João being a Portuguese first name, and Pimentel Spanish or Portuguese.