What is another word for by the bye?
Pronunciation: [ba͡ɪ ðə bˈa͡ɪ] (IPA) 
'By the bye' is a phrase used to indicate a digression from the main topic of conversation. It is often replaced by other synonyms such as 'incidentally', 'by the way', 'in passing', 'apropos of nothing' and 'en passant'. 'Incidentally' implies that the information is shared as an afterthought, and not necessarily relevant to the conversation. 'By the way' is similar in meaning and suggests a slight deviation from the main discussion. 'In passing' implies that the speaker mentioned something briefly and didn't make a big deal of it. 'Apropos of nothing' is used when a speaker changes the subject abruptly and is typically used humorously. Finally, 'en passant' is a French term often used in academic or formal settings to show a small deviation from the main topic of discussion.
