hairy(毛深い)が語源

roughへの移行を見ると、肌触りかな？

感覚的なきつさ

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過酷な世界

感覚的にきつすぎる→サングラス

ROUGH, HARSH, UNEVEN, RUGGED, SCABROUS mean not smooth or even.

ROUGH implies points, bristles, ridges, or projections on the surface.

e.g. a rough wooden board

HARSH implies a surface or texture distinctly unpleasant to the touch.

e.g. a harsh fabric that chafes the skin

UNEVEN implies a lack of uniformity in height, breadth, or quality.

e.g. an old house with uneven floors

RUGGED implies irregularity or roughness of land surface and connotes difficulty of travel.

e.g. a rugged landscape

SCABROUS implies scaliness or prickliness of surface.

e.g. a scabrous leaf

1. unpleasantly rough or jarring to the senses: 感覚に対して不愉快ででこぼこした、神経に障る

〈音･光･色･味などが〉 «…に» 不快な, きつすぎる «to» ; 〈形･風景などが〉不格好な, 不快な

e.g. drenched in a harsh white neon light: 不快な白いネオンの光で満たされた

e.g. harsh guttural shouts.: 不快なしゃがれ声の叫び声

(手触りが)ざらざらした, 粗い(rough)

e.g. a harsh towel: 手触りの粗いタオル

2. cruel or severe:残酷な、厳しい

e.g. a time of harsh military discipline.: 過酷な軍事訓練の時間

(of a climate or conditions) difficult to survive in; hostile: (気候や状態が)生存するのが難しい; 敵意のある

〈状況･気候などが〉厳しい, 過酷な;

e.g. the harsh environment of the desert.: 砂漠の過酷な環境

(of reality or a fact) grim and unpalatable: (現実や事実が)残酷で受け入れがたい

〈現実･事実が〉厳しい.

e.g. the harsh realities of the world news.: 世界のニュースの残酷な現実

having an undesirably strong effect: 望ましくない強い影響を持つ

〈洗剤･石けんなどが〉きつい, 強すぎる

e.g. she finds soap too harsh and drying.: 彼女は石鹸が強すぎて乾燥しすぎることに気づく。

harshen | ˈhärSH(ə)n | verb

Middle English: from Middle Low German harsch ‘rough’, literally ‘hairy’, from haer ‘hair’.