Mid 18th century; earliest use found in Thomas Mortimer (1730–1810), writer on trade and finance. From non- + admissible. Compare earlier non-admissibleness.
Definition of non-admissible in US English:
non-admissible
adjectiveˌnɒnədˈmɪsɪbl
Not admissible; inadmissible.
Origin
Mid 18th century; earliest use found in Thomas Mortimer (1730–1810), writer on trade and finance. From non- + admissible. Compare earlier non-admissibleness.