Kyle
This is a Scottish place and surname meaning a strip of land. It is more usual as a name for boys than girls, for whom Kyla is also used.

Kirsty
Kirsty or Kirsten are both forms of the name Christine. Kirsty was originally a Scottish pet form, while Kirsten comes from Scandinavia. Christine, meaning a Christian.

Kieran
Kieran, this a form of the Irish name Ciaran, meaning darkhaired.
It was the name of 26 Irish saints and in the last two or three decades has become increasingly popular.

Katherine
A name of unknown meaning but from an early date associated with the Greek katharos meaning pure. The name came to England in the early 12th Century when the crusaders brought back the legend of St Katharine of Alexandria.