Definition

Adverb: Used to introduce a comment or question that is not directly related to the main subject of conversation, or to add a piece of information that has just been remembered.

Usage

"By the way" is a common conversational transition. It signals a shift to a new, often less important or related, point. It can also be used to politely introduce a question or reminder.

Examples

• "The meeting is at 3 PM. By the way, have you seen the new report?" (Here, it introduces a new, related question.)
• "I loved the restaurant you recommended. By the way, I saw your brother there last week." (This adds a related but separate piece of information.)
• "We need to finish this project. Oh, by the way, don't forget to call the client." (This is used to add a reminder.)

Advanced Usage

• As a discourse marker: It functions to manage the flow of conversation, allowing the speaker to insert a secondary topic without a jarring transition.
  • We were discussing budgets, and by the way, that reminds me—we need to approve the travel expenses.
• In written communication: It is used informally in emails or messages to append an afterthought.
  • Thanks for sending the files. By the way, the deadline has been moved to Friday.

Variants and Related Words

• Incidentally (adverb): A more formal synonym often used in similar contexts.
  • The software is very efficient. Incidentally, it was developed by a small startup.
• Parenthetically (adverb): Refers to adding information as an aside, often within parentheses. This is a more technical term.

Synonyms

• Incidentally
• As an aside
• On a related note
• While I think of it

Related Phrases

• That reminds me: Used to introduce a topic triggered by the current conversation.
  • You're talking about Paris? That reminds me, I need to renew my passport.
• Just one more thing: Often used to add a final point, famously associated with the character Columbo.
  • I think that covers everything. Just one more thing—did you check the security logs?

Notes

"By the way" is considered informal and is most common in spoken English and casual writing. In very formal writing, alternatives like "incidentally" or restructuring the sentence are preferred.

Adverb

1. introducing a different topic; in point of fact
   • incidentally, I won't go to the party