From Middle English liklinesse, lyklinesse; equivalent to likely + -ness.

likeliness (uncountable)

1. The condition or quality of being probable or likely to occur.
2. Likelihood, probability or chance of occurrence; plausibility or believability.
   • 2004, Klaus-Martin Goeters, Aviation psychology: practice and research:

     The proposed HEA is based on the assumption that each specific error has a certain impact on a system/aircraft state whilst the crew's likeliness to commit this error is decreasing with an increasing number of safeguards against it.

   • 2006, David W. Embley, A. Olivé, Sudha Ram, Conceptual modeling:

     To determine the likeliness of an individual in a concept, a membership function is required.

3. Suitability; agreeableness.
   • 2004, Peter Lipton, Inference to the best explanation:

     A new competitor may decrease the likeliness of an old hypothesis, but it will usually not change its loveliness.

4. Likeness; similarity.

• likelihood