invisible
adj.adj. impossible to see with your eyes. You use this to describe things that are hidden or made of something clear, like air.
adj. unable to be seen by the naked eye; not perceptible by vision.
The gas is invisible and has no smell.
Many people feel invisible in large cities where no one stops to say hello or acknowledge their presence.
The artist used a special type of ink that remains invisible until the paper is heated, revealing a secret message hidden within the landscape drawing.
From Middle English invisible, from Old French invisible, from Late Latin invīsibilis. Displaced native Old English unġesewenlīċ. Morphologically in- + visible.
Typically used as an attributive adjective before a noun or as a predicative adjective after a linking verb like 'be' or 'become'.