Latent is an adjective that you use to describe something that is capable of becoming active or at hand, though it is not currently so.
The adjective latent is a tricky word to define because it refers to something there but not there. That is, latent means something that is capable of becoming active or at hand but has not yet achieved that state. The word arrived in Middle English from the Latin word latēre which means "to lie hidden." It can have somewhat negative connotations because it is often used in a medical context, as in a latent illness or infection, but it can also mean good things, such as someone discovering they have latent talents or capabilities.