Wiktionary
indetectable
a. Not detectable.
Usage examples of "indetectable".
Aren't they apt to know that we have inherently indetectable ships and almost perfectly absorptive coatings?
At five second intervals they were projected outward, invisible globes of concentrated magnetic energy, indetectable in space.
On a base very far removed from the Hub, on a base securely anchored and concealed among the gravitic swirlings and shiftings of a subspace turbulence area, virtually indetectable, the monster could make a very valuable partner.