Phrase guide

by the by

adj · prep_phrase · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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No pronunciation record was provided for this word.

1

adj

Meaning 1

Incidental; unplanned.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: accidental, causeless, random, accidentary, adventitious, by accident, by the by, casual, chanceable, fortuitous, incidental, lippening, occasional, serendipitous, unforeseen, unintended, unintentional, unplanned

Antonyms: none provided

2

prep_phrase

Meaning 2

Used to introduce a new topic; incidentally, by the way.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

The second "by" is a noun meaning "a secondary issue". Phrase used since the 17th century.