Definition
The word 'thereunder' means 'under it' or 'under that' and is used in formal contexts, particularly in legal or official writing. It implies a position or condition subject to something previously mentioned. Think of it as being governed by or included within something else. It's used to avoid repeating what's being referred to. It adds a layer of formality to writing. For instance, rights granted 'thereunder' are those specified by a document.