其它稱呼尚有MOTSS(Member of the Same Sex),該縮語來自1970年代美國的人口調查表格[45],80年代用於Usenet作為同志新聞群組的名稱[46],90年代成為台灣和中國大陆同志社群BBS看板名和論壇名[47][48]。由於社會偏見,產生了對同性戀者的貶稱,例如faggot、dyke、queer[49],兔子、基佬等[50],都被用來或曾被用來貶損同性戀者。這些貶稱,有些可能被重新挪用,而成為具有正面意義的稱呼,例如queer本是英文單詞的怪異之意,但反而被英美同性戀者重新挪用[51],最終成為學術研究和電視節目用語,例如酷兒理論(Queer Theory)、同志亦凡人(Queer as Folk)、酷男的異想世界(Queer Eye for the Straight Guy)。但由於仍帶貶損意味或有激進顛覆的政治性格等原因,不是所有同志都接受這稱呼[52][53]。
由於隱密溝通與社交認同的需要,男同志發展出一套社群用語[57][58],像是指稱性愛角色的1號(攻/Top,插入者)、0號(受/Bottom,被插入者)、0.5號(Both/Versatile(英语:Top, bottom and versatile),插入或被插入都可);指稱交往關係的葛格(哥,偏主動照顧)、底迪(弟,偏被動受照顧),但哥/弟可能會依不同脈絡事件互換或不加區分;形容體型打扮的熊(Bear,體態魁武飽滿,蓄鬍打扮多毛者)、猴(近Twink (男同性恋俚语),體態精瘦,不蓄鬍少毛者)、狼(Wolf,精實黝黑,滿臉鬍渣有男人味者)等等[7][59][60]。隨著時間流逝或地域差異等因素,這些用語有可能捨棄不用、意義產生轉變、或為其它詞彙所取代[61]。
另外一些證據指出激素與性傾向形成有關,一種說法是出生前的睪固酮濃度影響胎兒腦部結構,在子宮時編譯好特定的性傾向、性別認同以及相關的行為、認知和性格特質[101][102]。許多科學家分別考慮了出生順序、慣用手、頭髮漩渦、陰莖長短、身高體重關係,無名指/食指長度比例等因素,來研究激素與性傾向的關聯(英语:Prenatal hormones and sexual orientation)[103],Blanchard的研究發現“每多有一个哥哥,該名男子被另外一名男子吸引的可能性就大一些”[104],研究者認為這可能與母體懷多次男胎產生的免疫反應有關[105][106],Blanchard也發現發生該現象的男性多數都是右撇子[107]。
出櫃源自於英文「Coming out (of the closet)」,指承認、接受和欣賞自身的性傾向或性別認同,並將之與他人分享的歷程。與之相對的,隱瞞而不願表達,稱之為「躲在衣櫃」或未出櫃(Closeted)[119]。一般而言,出櫃可分為三個階段:第一階段是認識自我,願意對自己坦承,第二階段是向他人出櫃,將同志身份告知親友同事,第三階段是公開生活,將同志身份自由公開地融入生活之中。[120]。近年來,美國人口普查呈現同性伴侶增多的現象,似乎反映了同性戀者被社會接納認可程度的巨大變化,越來越多同性戀者願意公開性傾向或公開與同性伴侶的關係[121][122]。
1992年,由Laumann主持的National Health and Social Life Survey利用隨機樣本抽出美國三千多人調查,報告過去一年內,2.7%男性有過男性性伴侶,1.3%女性有過女性性伴侶,自18歲起,4.9%男性有過男性性伴侶,4.1%女性有過女性性伴侶。自我認同為同性戀(2%)或雙性戀(0.8%)男性佔2.8%,自我認同為同性戀(0.9%)或雙性戀(0.5%)女性佔1.4%。該研究還發現認同自身為同性戀或雙性戀的男女,通常有良好的教育背景,屬於中等或高等社會階層,集中在城市地區,例如美國最大12個城市,9%男性和3%女性受訪者自我認同為同性戀或雙性戀[133][142]。
2006-2008年,美國疾病控制與預防中心執行National Survey of Family Growth,依機率抽樣13495個15-44歲的樣本,報告5.2%的男性,12.5%的女性曾有過同性性行為。自我認同為同性戀(1.8%)或雙性戀(2.3%)的男性佔4.1%,自我認同為同性戀(1.3%)或雙性戀(2.8%)的女性佔4.1%[133]。
英国的沃芬敦报告是西方国家对同性性行爲除罪化的转折点,很多西方文明国家现在已经对同性恋或同性性行为除罪。一系列的欧洲国家,例如荷兰、德国等已经改变法律或者允许同性婚姻或者在法律上承認长期的同性伴侶关系;一些国家開始允许同性伴侣收养子女。而公开承认是同性恋、双性恋或过去曾经进行过同性性行为的政治家的人数也在上升。这包括了前英国国防秘书附属梅杰(John Major)、波蒂略(Michael Portillo);公开的同性恋政治家大卫·诺里斯(David Norris(英语:David Norris (politician)))是爱尔兰参议院议员;而现任以及前任爱尔兰总统玛丽·麦阿里斯(Mary McAleese)和玛丽·罗宾逊是爱尔兰同性恋法律改革运动(Campaign for Homosexual Law Reform(英语:Campaign for Homosexual Law Reform))的创始人。这个组织曾在爱尔兰对同性性行为除罪过程中起重要作用。[來源請求]
一項研究回顧表明,女同性戀或男同性戀撫養的孩子的表現較難跟傳统性別角色配合,更有可能對同性戀關係持開放態度,此一現象部分是跟遺傳因素(美國80%同性伴侶撫養的兒童都是有血缘关系的[157])和社會化進程(在相對較寬容的學校、鄰里和社會環境中長大)有关,但大多數由同性伴侶撫養的孩子会成为異性戀者[158]。夏洛特·帕特森(英语:Charlotte J. Patterson)为美國心理學會進行的2005年回顧發現,現有數據並不能夠支持「女同性戀或男同性戀所撫養的孩子有較高机会成为同性戀」的説法[159]。一項研究表明,由同性戀者撫養的孩子更傾向採用非異性戀模式的自我性别認同(其跟性傾向不同),特別是女同性戀者撫養的女兒(男兒較不受代間移轉影響)[160]。
二十世紀初,同性戀在西方社會仍普遍受法律壓迫;在1952年精神醫學會出版第一版精神疾病的診斷列表(DSM-I),同性戀被列為其中。然而該分類系統很快就受到國家心理衛生局(英语:National Institute of Mental Health)贊助研究的強烈檢視。該研究以及後續研究都未能發現任何實證資料能支持DSM-I的見解。隨著研究資料益發充實,醫療心理衛生專業人員和社會、行為科學家都同意DSM-I對同性戀的見解是來自於社會偏見。1973年,「美國精神醫學學會」承認科學研究的證據,將同性戀從精神疾病的診斷列表(DSM-III-R)中去除。[188]。
2012年5月17日,世衛駐美洲的辦事處,泛美洲衛生組織,就性向治療和嘗試改變個人性傾向的方法,發表一份用詞強烈的英文聲明《為一種不存在的疾病治療("Cures" for an Illness that Does Not Exist)》。聲明強調,同性戀性傾向仍是人類性向的其中一種正常類別,而且對當時人和其親近的人士都不會構成健康上的傷害,更毋需治療。世衛在聲明中再三指出,改變個人性傾向的方法,不單沒有科學證據支持其效果,而且沒有醫學意義,並會對身體及精神健康甚至生命形成嚴重的威脅,同時亦是對受影響人士的個人尊嚴和基本人權的一種侵犯。世衛亦藉發表該聲明提醒公眾,雖然有少數人士可以能夠在表面行為上限制表現出自身的性向,但個人性傾向本身一般都被視為個人整體特徵的一部分和不能改變;聲明內容同時譴責提供性向治療的醫護人員,是把他們自己與社會偏見看齊,並且反映他們對個人性傾向和性健康議題的絕對無知。世界衛生組織亦提醒各國的醫護人員,這麼作等同於違反醫學道德的第一道原則:「首要的事,不要造成傷害(First, do no harm)。[191]世衛同時透過聲明呼籲各地政府,應強烈反對當地的診所和醫院提供性向治療,並應立法懲處或制裁提供性向治療的醫療機構。世衛並且建議各地政府應多向公眾進行個人性向教育,以消除公眾對同性戀者的性傾向歧視。[192]
Definitions Related to Sexual Orientation and Gender Diversity in APA Documents(PDF). 美国心理学协会: 6. 2015 [February 6, 2020]. (原始内容存档(PDF)于2021-01-22). Sexual orientation refers to the sex of those to whom one is sexually and romantically attracted. [...] [It is] one's enduring sexual attraction to male partners, female partners, or both. Sexual orientation may be heterosexual, samesex (gay or lesbian), or bisexual. [...] A person may be attracted to men, women, both, neither, or to people who are genderqueer, androgynous, or have other gender identities. Individuals may identify as lesbian, gay, heterosexual, bisexual, queer, pansexual, or asexual, among others. [...] Categories of sexual orientation typically have included attraction to members of one's own sex (gay men or lesbians), attraction to members of the other sex (heterosexuals), and attraction to members of both sexes (bisexuals). While these categories continue to be widely used, research has suggested that sexual orientation does not always appear in such definable categories and instead occurs on a continuum [...]. Some people identify as pansexual or queer in terms of their sexual orientation, which means they define their sexual orientation outside of the gender binary of 'male' and 'female' only.
J. Michael Bailey; Marc Epprecht; Eric Vilain; S. Marc Breedlove; Lisa M. Diamond; Paul L. Vasey. Sexual Orientation, Controversy, and Science. Psychological Science in the Public Interest. 2016, 17 (2): 45–101 [2017-05-09]. (原始内容存档于2021-02-15). No causal theory of sexual orientation has yet gained widespread support. The most scientifically plausible causal hypotheses are difficult to test. However, there is considerably more evidence supporting nonsocial causes of sexual orientation than social causes.
What Scientists Know—And Don't Know—About Sexual Orientation. Association for Psychological Science. 2016-04-25 [2017-05-09]. (原始内容存档于2021-02-13). Various biological factors--including prenatal hormones and specific genetic profiles--are likely to contribute to sexual orientation, though they are not the sole cause. Scientific evidence suggests that biological and non-social environmental factors jointly influence sexual orientation. -- Scientific findings do not support the notion that sexual orientation can be taught or learned through social means. And there is little evidence to suggest that non-heterosexual orientations become more common with increased social tolerance.
* Lisa Diamond. Concepts of Female Sexual Orientation. 2013 [2016-05-11]. (原始内容存档于2021-02-13). Historically, researchers have presumed that sexual orientation shows fundamental continuity in its expression over time. Although this is generally true for most individuals, some studies have found that a number of individuals - more often women than men - report notable shifts in same-sex attractions, behaviors, and identities over time.
Lisa Diamond - Psychology's Feminist Voices. [2016-05-11]. (原始内容存档于2020-10-22). Sexual Fluidity attracted substantial media attention. However, the data Diamond collected began to be picked up by anti-gay groups, who espoused that being gay is a choice. Diamond has tried to make her findings clear: she did not find that women "choose" to be gay, or "choose" to become straight, rather, relationships and attractions happen, and there is really no "choice" involved..."This (research) does not mean that sexuality is chosen" - an important point that needs repeating.
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Ritch C. Savin-Williams. How Many Gays Are There? It Depends(PDF). Contemporary Perspectives on Lesbian, Gay, and Bisexual Identities. 2009: 5–41 [2015-11-12]. doi:10.1007/978-0-387-09556-1_2. (原始内容存档(PDF)于2021-09-19). These definitional dilemmas are not restricted to one age group or one culture. In the United States, the United Kingdom, and France, exclusive same-sex behavior rarely characterized more than 1% of the adult population. If the definition was broadened to include individuals who had both same- and opposite-sex behavior, who had some degree of same-sex attraction, or at least one of the two, then the proportion of gays expanded considerably– nearly one-fifth of the population of men and women (p. 18). 該數據引自 Sell, R. L., Wells, J. A., & Wypij, D. (1995). The prevalence of homosexual behavior and attraction in the United States, the United Kingdom and France: Results of national population-
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DONALDSON JAMES, SUSAN. Census 2010: One-Quarter of Gay Couples Raising Children. ABC News. 2011-06-23 [2013-07-11]. (原始内容存档于2017-06-30). Still, more than 80 percent of the children being raised by gay couples are not adopted, according to Gates.
Stacey J, Biblarz TJ. (How) Does the Sexual Orientation of Parents Matter?(PDF). American Sociological Review. 2001, 66 (2): 159–183 [2017-05-27]. doi:10.2307/2657413. (原始内容(PDF)存档于2011-09-28). This may be partly due to genetic and family socialization processes, but what sociologists refer to as "contextual effects" not yet investigated by psychologists may also be important...even though children of lesbian and gay parents appear to express a significant increase in homoeroticism, the majority of all children nonetheless identify as heterosexual, as most theories across the essentialistt" to "social constructionist" spectrum seem (perhaps too hastily) to expect.
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Maurianne Adams, Lee Anne Bell, Pat Griffin. Teaching for Diversity and Social Justice. Routledge. 2007: 198–199 [2014-12-27]. ISBN 1135928509. (原始内容存档于2015-05-14). Because of the complicated interplay among gender identity, gender roles, and sexual identity, transgender people are often assumed to be lesbian or gay (See Overview: Sexism, Heterosexism, and Transgender Oppression). ... Because transgender identity challenges a binary conception of sexuality and gender, educators must clarify their own understanding of these concepts. ... Facilitators must be able to help participants understand the connections among sexism, heterosexism, and transgender oppression and the ways in which gender roles are maintained, in part, through homophobia.
Claire M. Renzetti, Jeffrey L. Edleson. Encyclopedia of Interpersonal Violence. SAGE Publications. 2008: 338 [2014-12-27]. ISBN 1452265917. (原始内容存档于2015-05-15). In a culture of homophobia (an irrational fear of gay, lesbian, bisexual, and transgender [GLBT] people), GLBT people often face a heightened risk of violence specific to their sexual identities.
Kerri Durnell Schuiling, Frances E. Likis. Women's Gynecologic Health. Jones & Bartlett Publishers. 2011: 187–188 [2014-12-27]. ISBN 0763756377. (原始内容存档于2015-05-14). Homophobia is an individual's irrational fear or hate of homosexual people. This may include bisexual or transgender persons, but sometimes the more distinct terms of biphobia or transphobia, respectively, are used.
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