Impenetrable
来自Big Physics
late Middle English: via French from Latin impenetrabilis, from in- ‘not’ + penetrabilis ‘able to be pierced’, from the verb penetrare (see penetrate).
wiktionary
From Middle French impenetrable, from Latin impenetrabilis.
etymonline
impenetrable (adj.)
"impossible to penetrate," mid-15c., from Old French impenetrable (14c.) or directly from Latin impenetrabilis "that cannot be penetrated," from assimilated form of in- "not, opposite of" (see in- (1)) + penetrabilis "penetrable" (see penetrable). Related: Impenetrably; impenetrability.
