Is there any word that begins with the letter x an adjective?

You're right, there aren't many adjectives that start with the letter "x"! Here are a few options, depending on what you consider an adjective:

* Xenial: This is a less common adjective meaning "hospitable, welcoming."

* Xenophobic: This adjective describes someone who is fearful or hostile towards foreigners or strangers.

* Xerophilic: This is a more technical adjective describing organisms that thrive in dry environments.

* Xeric: This adjective describes a dry, arid habitat.

While these words are technically adjectives, they are not very common in everyday language. It's a good example of how the letter "x" is relatively rare at the beginning of words!