Incidentally
来自Big Physics
Safin(讨论 | 贡献)2022年4月27日 (三) 12:56的版本 (建立内容为“Category:etymology == google == [https://www.google.com.hk/search?q=incidentally+etymology&newwindow=1&hl=en ref] early 17th century: originally from medieva…”的新页面)
early 17th century: originally from medieval Latin incidentalis, from Latin incident- ‘falling upon, happening to’ (from the verb incidere ).
wiktionary
incidental + -ly
etymonline
incidentally (adv.)
1520s, "by the way, casually;" see incidental + -ly (2). Sense of "as a new but related point" attested by 1925.