Impossible to avoid or evade:
— An unavoidable accident.

synonyms: ineluctable, inescapable.

Roget 601: necessary, needful etc. (requisite) 630.    fated; destined etc. v.; elect; spellbound compulsory etc. (compel) 744; uncontrollable, inevitable, unavoidable, irresistible, irrevocable, inexorable; avoidless^†, resistless.    involuntary, instinctive, automatic, blind, mechanical; unconscious, unwitting, unthinking; unintentional etc. (undesigned) 621; impulsive etc. 612.    ... show more

Roget 474: certain, sure, assured etc. v.; solid, well-founded.    unqualified, absolute, positive, determinate, definite, clear, unequivocal, categorical, unmistakable, decisive, decided, ascertained.    inevitable, unavoidable, avoidless^†; ineluctable.    unerring, infallible; unchangeable etc. 150; to be depended on, trustworthy, reliable, bound.    unimpeachable, undeniable, unquestionable; indisputable, incontestable, incontrovertible, indubitable; irrefutable etc. (proven) 478; conclusive, without power of appeal.    indubious^†; without doubt, beyond a doubt, without a shade or shadow of doubt, without question, beyond question; past dispute; clear as day; beyond all question, beyond all dispute; undoubted, uncontested, unquestioned, undisputed; questionless^†, doubtless.    authoritative, authentic, official.    sure as fate, sure as death and taxes, sure as a gun.    evident, self-evident, axiomatic; clear, clear as day, clear as the sun at noonday.    ... show more