undefinable

equivalents

undefined

vague

synonyms

indefinable

etymologically-related-terms

undefinability

same-contexts

bone-deep

fleeting

illusory

impalpable

indefinable

indefinite

indescribable

indiscernible

inexplicable

intangible

nameless

nebulous

overpower

premonitory

sicken

unattainable

uncomprehended

undefined

undiscoverable

unexplainable

unfathomable

unjustified

unworded