Which part of speech is the word visiting when it comes before ships?

The word "visiting" in the phrase "visiting ships" is a participle.

Here's why:

* Participles are words that are formed from verbs and act as adjectives.

* In this case, "visiting" describes the ships, telling us that they are the ones that are doing the visiting.

* The full verb phrase would be "ships that are visiting".

Therefore, "visiting" modifies the noun "ships" and functions as an adjective.