Grosso modo is a phrase of Latin origin, meaning "approximately". The phrase has been adopted in many languages (like English, French, Dutch, etc), as the referred link testifies.
What is the origin of the phrase grosso modo?
Grosso modo comes from the medieval latin grossus modus, meaning 'in a rough way'. It's use has been established as early as the XIVth century, according to Reverso.
What is Grosso Modo?
: in a coarse way : roughly : approximately.