adjective
Synonyms: imperceptible , inappreciable, indiscernible, insensible, intangible, invisible, unapparent, unappreciable, unobservable, unperceivable
Antonyms: discernible
adjective
Synonyms: imperceptible , inappreciable, indiscernible, insensible, intangible, invisible, unapparent, unappreciable, unobservable, unperceivable
Antonyms: discernible
Merriam Webster. Collegiate thesaurus English vocabulary. Английский энциклопедический словарь тезаурус. 2003