IPA: /ˈɪntrəstɪŋnəs/
KK: /ˈɪntrəstɪŋnəs/
The quality or state of being engaging or holding attention.
The interestingness of the documentary kept the audience captivated throughout.
Interestingness → It is formed from "interest" (from Latin "interesse", meaning to be between or to matter) and the suffix "-ness" (meaning the state or quality of). The word "interestingness" refers to the quality or state of being interesting or engaging.
Think of something that 'matters' or 'is between' ('interesse') and how that quality makes it engaging — that's what interestingness means.