希薄 きはく
kihaku

Noun
na-Adjective

1. thin (air); weak (liquid); dilute; sparse (population); rarefied

たか のぼるにつれて、空気 くうき希薄 きはくになる。
takakunoboruni tsurete kūkiwa kihakuni naru.
As you go up higher, the air becomes thinner.
Noun
na-Adjective

2. lacking (enthusiasm, consideration, substance, etc.); insubstantial; deficient; tenuous (link)

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