1. Not allowing fluid to pass through: "an impermeable membrane".
2. Not liable to be affected by pain or distress; insusceptible or imperturbable: "women who appear impermeable to pain".

1. (esp. of a theory or argument) Appearing neat and comprehensive by ignoring the complexities of an issue; superficial.
2. (of a person) Having a superficial or simplistic knowledge or approach.

Contra

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