Other forms: coincided, coinciding, coincides
To coincide is to happen at exactly the same time. Coincide with, the dates coincide, made to coincide.
It also means to agree, as when two accounts coincide, and in geometry two shapes coincide when they occupy the same space exactly. The chance sense is the common one, and it is why a coincidence is two things that merely coincide.
1verbcoincideTo happen at exactly the same time.
“My birthday coincides with a public holiday this year, so everyone is free.”
coincide is a happening together.
Medieval Latin coincidere means to fall together — con, with, plus incidere, to fall upon, from cadere, to fall.
Proto-Indo-European
*ḱh₂d-
Medieval Latin
coincido
French
coïncider
English, today
coincide
Built from
From French coïncider, from Medieval Latin coincido, from con- + incido, from in- (“into, to”) + cado (“to fall, fall down, drop”).
Etymology from Wiktionary, CC BY-SA