Where did the word gay come from? Origin and development in the Czech language

Gay (pronounced: gey), while a commonly used word in Czech, certainly doesn't originate from it. So where did it come from? 

You might guess that the word gay comes from English, and you wouldn't be wrong. However, in this language, it doesn't only refer to masculine individuals sexually oriented towards other masculine individuals. The word gay can also be translated as "merry" or "joyful," as we can read in a number of dictionaries. 

But how did this word come about in English?

According to Gayly.com, it entered English in the twelfth century from Old French gai, which also referred to something cheerful or carefree. However, the connection to sex and sexual orientation only appeared in English in the seventeenth century, likely because it was used to describe people of "loose morals." In the Oxford English Dictionary, the word gay first appears with a sexual meaning in 1951.

And when did the word gay first appear in Czech?

We cannot say for sure, but the first occurrence of the word gay in the Czech Language Corpus database is found in Lidové noviny from 1992. Issue 153 reports that HIV spread in gay clubs, but at the same time, the phrase gay-related immune deficiency syndrome is translated by the newspaper as syndrom nedostatku odolnosti homosexuálů (homosexual immunity deficiency syndrome), not gayů (gays). In another issue of the same year, however, the newspaper already uses the word gay as a noun when reporting on the visit of German director Rosa von Praunheim to then-Czechoslovakia.

For now, it doesn't seem that the word gay has a pejorative connotation in Czech, nor has any masculine person sexually oriented towards other masculine persons visibly spoken out against it. On the other hand, languages change, and it's possible that in a few centuries, we might use a different term to describe gays.

Btw. Do you know where the word lesbian came from?