corroborant
Anything that gives strength or support; a tonic.
archaic
The sensible qualities of argentina promise no great virtue of this kind; for to the taste it discovers only a slight roughishness, from whence it may be presumed to be entitled to a place only among the milder corroborants.
Something that corroborates.
archaic
As a scrupulous and faithful antiquary, Morales was accustomed to require evidence, and to investigate it; and for these he could find no other testimony than tradition and antiquity, which, as presumptive proofs, were strong corroborants of faith, but did not suffice of themselves.
Where it comes from
From Latin corroborans. See corroborate.
Adapted from the Wiktionary entry corroborant (CC BY-SA 4.0).