Why "A grosso modo" is incorrect?: the RAE explains it

Why "A grosso modo" is incorrect?: the RAE explains it

Sometimes it is common to read in the media or messages on social networks phrases such as "Roughly speaking, those who suffer from this syndrome perceive their achievements as undeserved" or "A good number of visitors arrived that, roughly speaking, would be a hundred" . In both cases, the locution expresses an "approximate" calculation. As in this case: "The species of this animal, roughly, could be divided into two large groups." However, as the Fundéu of the Royal Spanish Academy (RAE) recalls, that is not correct.

As established in its Fundéu recommendations, Grosso modo, with two s's in grosso, "is a Latin locution that means approximately or roughly". In their explanation, they point out that despite its widespread use, it is always incorrect to put the preposition a before it, as stated in the Nueva grammar de la lengua española. The Latin locution grosso modo is never preceded by the preposition a.

It is also remembered that it is appropriate to write it in italics or, if this type of letter is not available, between quotation marks, as indicated by the Orthography and the Pan-Hispanic Dictionary of Doubts here. Therefore, in the previous examples, it would have been appropriate to write «Roughly, those who suffer from this syndrome perceive their achievements as undeserved», «Human rights can be understood, roughly, as those that are inherent to any person» and « It has given rise to a fleet that, roughly speaking, could be divided into two large groups.