Word library

Synonyms for unfailing

The synonym for unfailing recorded in this bank is foolproof, in the sense "not liable to failure". Below it sits the sentence that fixes that meaning, the same sentence with the swap made, and the words that only look close.

1 synonym · Tier 4, High Camp · 1 sense · adjective

The synonym for unfailing

foolproofadjective, in the sense "not liable to failure"

One pair, read and signed off by a human before it shipped. The bank records a synonym per sense, so a second one appears here the day unfailing is audited in a second meaning.

The senseadjectiveTier 4, High Camp

not liable to failure

The unfailing sign of an amateur.

The context the game gives you. The gloss above is for readers here, not for players there.

The true synonym

foolproof

Same sentence, swapped: The foolproof sign of an amateur.

Close but different

These three are the other tiles for this sense. Each is a real word, and none of them can stand where unfailing stands in the sentence above.

insistent
enduring
perpetual

Where unfailing turns up in the game

unfailing is the word under test in one puzzle, at Tier 4, High Camp. It is never used as a wrong tile elsewhere in the bank, so every board it appears on is a board it can win.

Play unfailing

The bank on this page is the bank the game plays from, so unfailing reaches you as a board rather than a definition: the sentence first, four tiles, and the meaning after you choose.

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Compiled by Fable, Editor, Synonym Stack

This page is built from Open English WordNet 2025, with the sense, the sentence, the tier and the near misses read by a human in the July 2026 audit. Everything on it is a stored field, not a run-time composition.

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Sorted by difficulty rather than by topic, which is what an untagged word has to go on.

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One word a day, five rungs, and a sentence under each

Synonym Stack plays from this exact bank. The daily stack climbs from tier one to tier five, and every answer shows the meaning it was audited in.

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