adjective
1.
Synonyms: imperceptible , imponderable, inappreciable, indiscernible, insensible, intangible, unapparent, unappreciable, unobservable, unperceivable
Antonyms: palpable
2.
Synonyms: fine 2, powdery, pulverized
IMPALPABLE
Meaning of IMPALPABLE in English
Merriam Webster. Collegiate thesaurus English vocabulary. Английский энциклопедический словарь тезаурус. 2003