/ɪnˈstæŋtʃəl/ IN-stang-chəl

Definitions

1. adjective

tending to be or seem convincing, but lacking firm evidence

“The detective suspected that the alibi was instancial, but further investigation revealed the truth.”

2. noun

a piece of evidence or reasoning that seems convincing but lacks firm basis

“The lawyer tried to use the instancial claim as a basis for the case, but it fell apart under cross-examination.”