plausibility

[Cf. F. plausibilité.]

1. Something worthy of praise. [Obs.]

Integrity, fidelity, and other gracious plausibilities.

2. The quality of being plausible; speciousness.

To give any plausibility to a scheme.

3. Anything plausible or specious. R. Browning.

noun

Appearance of truth or authenticity: believability, color, credibility, credibleness, creditability, creditableness, plausibleness, verisimilitude. See likely/unlikely.

The noun has one meaning:

Meaning #1: apparent validity
  Synonym: plausibleness
  Antonym: implausibility (meaning #1)