IPA: /kənˈvɪn.sɪŋ.nəs/
KK: /kənˈvɪnsɪŋnəs/
The quality of being able to make someone believe that something is true or real.
The convincingness of her argument won over many skeptics.
Convincingness → It is formed from "con-" (meaning together) and "vincere" (meaning to conquer or overcome), combined with the suffix "-ing" (indicating the action of) and "-ness" (indicating a state or quality). The word "convincingness" refers to the quality of being able to persuade or overcome doubt effectively.
Think of the idea of 'overcoming' doubts ('vincere') together ('con-') — that's why convincingness means the quality of being persuasive.