guaranty

takuu puhekieltä An undertaking to answer for the payment of some debt, or the performance of some contract or duty, of another, in case of the failure of such other to pay or perform; a warranty; a security.
Something serving as a security for such an undertaking.
{{quote-book|year=1864|author=Various|title=The Atlantic Monthly, Volume 14, No. 85, November, 1864|chapter=|edition=|url=http://www.gutenberg.org/etext/24885
An assurance or guarantee.
{{quote-book|year=1904|author=Olive Tilford Dargan|title=Semiramis and Other Plays|chapter=|edition=|url=http://www.gutenberg.org/etext/23234
1945, (w), “http://www.jstor.org/stable/2988964 The Philosophical Basis of Masaryk’s Political Ideals” in w:Ethics (journal)|Ethics LV, № 4 (July 1945), page 299, right column:

The concept of God and immortality is for him a guaranty of this eternal difference between right and wrong.