What is another word for is invisible to the eye?
Pronunciation: [ɪz ɪnvˈɪzəbə͡l tə ðɪ ˈa͡ɪ] (IPA) 
The phrase "is invisible to the eye" suggests that something cannot be seen by the naked eye or is imperceptible. Synonyms for this phrase include "undetectable," "unobservable," "unseen," "unperceivable," "imperceptible," "intangible," "hidden," and "obscured." These words are often used to describe objects, emotions, or concepts that are not easily observable or tangible. For example, one might say that the intricacies of a person's inner thoughts and feelings are often invisible to the eye. Similarly, the microscopic particles and organisms that make up our world can often go unnoticed and invisible to the naked eye.
