In other words
A very common alternative, meaning 'that is to say' or 'I mean'. It's used to clarify or explain a previous statement.
Extremely common in informal, spoken Spanish, similar to 'I mean' or 'like'. It connects ideas or rephrases something in a more casual way.
A more formal or literary phrase meaning 'put another way'. Ideal for presentations, writing, or more serious conversations.
Use this when you are rephrasing something in a more concise way. It means 'in summary' or 'in short'.
I don't have much money right now. In other words, I can't buy the new car.
The flight leaves at 6:00. That is to say, we have to be at the airport at 4:00.
I completely forgot about our appointment. I mean, I'm so embarrassed!
The new policy requires approval from three departments. Put another way, it will be a slow process.
'En otras palabras' and 'es decir' are universally understood and used in both formal and informal contexts across the Spanish-speaking world.
'O sea' is extremely common in informal, everyday speech. It's often used as a filler word, similar to 'like' in English.
'O sea' is also very common, but can sometimes be seen as a 'muletilla' (filler word) associated with younger speakers or overly casual speech.
Argentinians use 'o sea' frequently. You will also hear 'quiero decir' (I mean to say) used very often to clarify a point in conversation.
'Es decir' is very common in all registers. 'O sea' is also widely used, especially among younger people in informal settings.
Using 'o sea' in formal writing. — 'O sea' is primarily for spoken, informal Spanish. In a formal essay, email, or presentation, it's better to use 'es decir', 'en otras palabras', or 'dicho de otro modo' to maintain a professional tone.
Incorrectly translating 'words' literally in other contexts. — Learners sometimes try to create phrases like 'en las palabras de...' (in the words of...). The correct expression is 'en palabras de...'. The 'las' is not needed. 'En otras palabras' is a set phrase.
Confusing 'es decir' with 'es a decir'. — The correct phrase is 'es decir'. Adding the 'a' is a common error for learners. It directly translates to 'it is to say', and the 'a' is grammatically incorrect in this structure.