So when you see signs in English that say "Welcome!" the part of speech is technically an interjection, but it comes from the adjective. Basically it is the shortened form of "You are welcome here!" Simple enough.
In some languages that have gender endings for adjectives, such as French, it's more obvious that signs that say "Welcome!" are using the adjectival form--as opposed to the noun or verb. Sooo... what gender do you make it? Masculine, of course, as languages often tend to assume the unspecified third person reader is masculine.
"Bienvenu!" it would say to the reader in French.
But! Times are a-changing and the world is so post-modern and women and men are feeling equal now a days... so equal that this masculine form was seeming unfair. --in France, anyway.
Indeed, signs are now saying "Bienvenue!" which, while it is also the feminine adjectival form, is more importantly the noun form--which in French doesn't require gender specification. In essence, these signs instead of implying "You are welcome here" are really giving a welcome. The noun welcome. They imply "This is a welcome for you. Happy arrival!"
Oh genders and post-modernism! This opens the door to so many changes... if people really want to push for gender equality and then push for that to carry over to language--which is absurd because language gender tags are not really related to men and women or masculine and feminine in that sense--then they are going to have to change the nature of the language itself.
Which may be what they want. Not only equality in the ends but equality in the means. If language really does create culture and culture, language, then to really alter the cultural mindset, the language would have to be reflective as well.
It's quite a daunting task.
Oh the French!