葉と茎の両方が棘で覆われているイラクサ：セイ⺕ウイラクサ。この植物は中国語で「噛む猫」と呼ばれ、棘で覆われた茎と軸とともに交尾の過程に不可欠な部分です。飼い猫の陰茎には後ろ向きの棘が約150個あり、おそらく、挿入する前に早く引き抜くことによるペナルティを防ぐためです：「脚を広げた状態で刺した陰茎から軸が出て、陰茎を広げ、液体の流れのある棒。」猫は騒ーしく交尾し、成猫のメスは「女王」と呼ばれますが、その理由はおそらく明白です。発情期は23週間ごとに繰り返され、女王と飼い主の両方に苦痛を与えます。この発情期の間、女王は家から逃げ出して交尾すること、または不注意でオスの猫を同じ家庭で飼っている場合はオスの飼い主と交尾することに全神経を集中します。彼女は交尾することだけに集中し、大声で鳴き（コ ール）、ドアの近くに潜み、あなたの家の近くに群がって女王を妊娠させる特権を求めて戦う騒ーしい猫のロメオの1匹と出会う機会を待ちます。…女王は交尾の意思を独特の姿勢で示します。頭を下げ、前足を曲げ、後ろ足を上げて外陰部を露出させ（この持ち上げた姿勢は前弯と呼ばれます）、尾を上げて体の横に置き、すべてオス猫の陰茎が入りやすいように設計されています。後ろ足は、その場で歩いているかのようにリズミカルに踏みます。オス猫は後ろからメス猫にまたがり、歯で首の後ろをつかみます。この噛みつき行動は、協力してもらうためでもあるかもしれませんが、メス猫の脳の一部を刺激して排卵を誘発する可能性もあります。オス猫は、魚の針のようなとげのある陰茎を持っており、引き抜くと、メス猫はしばしば叫びます（エクスタシーからか痛みからかは不明です）。とげのある陰茎が排卵を刺激すると考えられています。
　【　https://www.thesprucepets.com/the-cat-mat　 ING-GAME-5523912023-05-18　】

Nettle that has both leaves and stems covered with pricks: Urtica thunbergiana. This plant is named「biting cats」in Chinese, an integral part of the copulation process together with a stem, shaft that is covered with pricks. Domestic cats have about 150 or so backward-facing pricks on the penis, presumably to prevent penalties for an early withdrawal before leaving a deposit:「emerging shafts on prick in spread legs and reaming, rod with stream of fluid.」Cats copulate noisily, and adult female cats are called 'queens' perhaps for obvious reasons:「…estrus cycles will repeat as often as every two or three weeks, causing distress to both the queen and her human companions. During these cycles, Queenie's entire focus will be on escaping the house to mate, or to mate with a male companion, if you are careless enough to have whole male cats in the same household. She will be single-minded in her need to mate, will loudly vocalize (call), and lurk near doors, just waiting for the chance to meet up with one of the noisy feline Romeos who will cluster near your house, fighting for the privilege of impregnating your queen. …The queen will signal her willingness to mate with a unique posture: head down, forelegs bent, rear quarters raised to expose the vulva (this raised posture is called lordosis), with the tail raised and held to the side of the body, all designed to accommodate entry by the tom cat's penis. Her rear legs will tread rhythmically, as if walking in place. The tom cat will mount the female from the rear, holding her on the back of the neck with his teeth. This biting behavior may in part be to ensure cooperation, but may also stimulate a part of the female's brain that induces ovulation. Whole male cats have barbed penises (much like a fishhook), and upon withdrawal, the female cat will often scream (whether from ecstasy or pain is questionable). It is also believed that the barbed penis stimulates ovulation.」
　　[　https://www.thesprucepets.com/the-cat-mating-game-552391 2023-05-18　]　

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaninglless mnemonics)
Chinese: Urtica thunbergiana
Unihan extended: thorn
EDRDG: thorn