形容詞“性的（sexual）”起初只有非常有限的用法，決沒有超出某一種類的分類用法的含義之外。直到18世紀，這個詞語才擴展了它的含義，並開始也指生殖的一個過程。這一改變部分地歸功於科學進步的結果。例如，1735年瑞典植物學家卡爾·馮·林奈（Carl von Linné）設計出了一套他所稱的植物性徵分類法（methodus sexualis），即植物的一套屬種分類方法或系統，按照各類植物的生殖結構的特徵和數目把它們按序列分類。這套分類方法（現今已經廢止）給當時大多數學者甚至許多外行留下了深刻的印象。不過，當時仍然有一些頗為特殊的反對派存在。林奈的分類系統遭到一些宗教領袖的猛烈攻擊，他們發表正式的文件指出這套分類系統考慮讓一隻雌蕊與數隻雄蕊在同一朵花內同居。這顯然是下流的，並且是對上帝的誹謗；因為上帝不可能創造如此墮落的生靈。因此，他們呼籲生物教師不要向學生提及林奈的植物分類法。

雌蕊(pistil)     雄蕊(stamen)

Introduction - What is sexual behavior?

History of the Term 2

The adjective "sexual" originally had only a very limited use and never implied anything more than a category of some kind. It was not until the 18th century that the word broadened its meaning and began to refer also to the process of reproduction. This was, in part, a consequence of scientific progress. For example, in 1735, the Swedish botanist Carl von Linné devised what he called a methodus sexualis, i.e., a sexual classification method or system in which plants were listed according to the character and number of their reproductive structures. This method (which is now obsolete) greatly impressed most scholars and even many laymen at the time. However, there was also some rather peculiar opposition. Linné's system was violently attacked by certain religious leaders who noted that it allowed for the cohabitation of one female pistil with several male stamens in one and the same flower. This was clearly indecent and a defamation of God who could not possibly have created such depravity. Biology teachers were therefore implored not to mention it to their young students.