That part of an instrument or machine which serves as the
means of operating it; as, a telegraph key; the keys of a pianoforte,
or of a typewriter.

A position or condition which affords entrance, control, pr
possession, etc.; as, the key of a line of defense; the key of a
country; the key of a political situation. Hence, that which serves to
unlock, open, discover, or solve something unknown or difficult; as,
the key to a riddle; the key to a problem.

s. & adv. What time, when? What time, when.

An instrument which is turned like a key in fastening or
adjusting any mechanism; as, a watch key; a bed key, etc.

كَيْ [key] (kâf’ın fethi ve yâ’nın tahfîfiyle) Bir kelimedir ki لِمَ فَعَلْتَ كَذَا kelimesinin cevâbıdır, pes 'âkıbet için olup lâm gibi fi’l-i müstakbeli mansûb kılar; tekûlu: فَعَلْتُ ذَلِكَ كَيْ يَكُونَ كَذَا

s. & prop. n. 1. A great king, monarch, sovereign. 2. Name or surname of several of the old legendary Persian monarchs.

(f. i. c. : keyân) : büyük hükümdar, pâdişâh, eski Acem şahlarından ikinci tabakada bulunanlarının adlarının başına getirilirdi. Key-husrev, Key-kubâd, Key-kâvûs. . gibi.

(f. zf.) : ne zaman, ne vakit. Tâ be-key veya Tâkey : ne zamana kadar.

conj. In order that…

An instrument by means of which the bolt of a lock is shot or
drawn; usually, a removable metal instrument fitted to the mechanism of
a particular lock and operated by turning in its place.