Arabic, as befits the language of revelation, enjoys linguistic richness regarding important occasions. For example, Al-Suyuti in Al-wishah fi Fawa’id Al-nikah [Jeweled Shawl on the Benefits of Marital Relations] lists approximately 800 terms and expressions for the intimate act, including many terms taken from the work of lexicologist and scholar of literature Ibn Al-Qitaa’ (إبن القطاع); if the linguistic derivatives and variations included with some of these terms are considered, there are many more than 800 in total. Some common terms are listed here.

جامع / جماع [noun/verb jimaa’/jaama’a] – the standard, neutral word for the intimate act, from the root to bring or come together
أتى / إتيان [ityan/ata] – the most frequently used allusion to sexual intercourse; literally to come to, approach
نكح / نكاح [nikaah/nakaha] – frequently used; often translated as marry/marriage, but only in the sense that this is the platform for and necessarily implies a sexual relationship, i.e. a marriage consummated; usually refers unequivocably to the intimate act itself:

نكح نكح فلان إمرأة ينكحها نكاحاً إذا تزوجها ونكحها باضعها أيضاً وكذلك دحمها وخجأها … قال الأزهري أصل النكاح في كلام العرب الوطء وقيل للتزوّج نكاح لأنه سبب الوطء المباح
لسان العرب لإبن منظور-
One undertakes nikah with a woman whenever he marries her; nikah also means he has sex with her, and likewise bangs her [dahamaha] or strikes her [khaja'aha]. … Al-Azhari said: The root of nikah in the language of the Arabs is to tread [wat', i.e. intercourse]; marriage can be said to be nikah, since it is the basis for permissible intercourse.
- Ibn Mandhur, Lisan Al-arab

النكاح في اللغة عبارة عن الضم والوطء يقال نكح المطر الأرض إذا وصل إليها ونكح النعاس عينه
تفسير الرازي سورة البقرة ٢٢١
Nikah, linguistically, expresses embracing/coming together and trampling down on; it can be said: "Rain nakah the earth" whenever it reaches it,or "Slumber nakah one's eyes"
- Tafsir Al-Razi, Surah Al-baqara 221

والنكاح في اللغة الضم والتداخل… وكثر إستعماله في الوطء وسمي به العقد لكونه سببه… وإذا قالوا نكح زوجته فالمراد الوطء
فتح الباري كتاب النكاح
Nikah linguistically means to embrace/come together and to interpenetrate/intertwine [tadakhul] … it was used abundantly to refer to intercourse, and the contract [‘aqd] was called by this name since it is the reason for it … whenever they say someone nakah his wife, the intended meaning is intercourse.
- Ibn Hajar, Fath Al-bari, The book of marital relations [nikah]

إجتمع [ijtama’ ] – to meet, come together mutually
وصل إلى [wasala ila] – to come to
باشر / مباشرة [mubaashara/baashara] – generally refers to fondling and other intimate contact (i.e. foreplay), not necessarily the intimate act, although this is usually included. From the same root as the words bashar (mankind) and bashara (skin)
وطء [wat’ ] – to trample or tread on
بضع / مباضعة [mubaada’a/bud’] – from the root meaning progeny and vagina (بُضع, bud’, marriage contract or genitals)
وقع [waqa’] – to fall upon
واقع [waaqa’] – to combat
استمتع [istamta’] – to enjoy; from the same root as mut’a [temporary marriage, or more literally, pleasure marriage]
أصاب [asaaba] – to come upon or befall
عاشر / معاشرة [mu’aashara/’aashara] – intimate contact
ناك / نيك [naik/naaka] – explicit, like “fuck”; used, for example, when the Prophet (SAW) wished to make sure the issue at hand was clearly understood; also used generously in the more expressive scholarly treatises
مس الختان الختان [mass al-khitan al-khitan] – “the circumcised part touching the circumcised part”, an example of the expressiveness of the Prophet (SAW)
إلتقاء الختانين [iltiqaa al-khitanain] – the meeting of the circumcised parts
رفث [rafth] – general word for what men desire of women in view of enjoying them, without allusion (i.e. a somewhat coarse term); sexual obscenities
غشيَ / غشيان [ghishyaan/ghashiya] – to cover; get on top of and cover
جهد ، إجتهد [ijtahada, jahada] – to exert, make an effort
دخل [dakhala] – to enter
بنى [bana] – to build on
نزا [naza] – to jump on, mount
لامس / ملامسة [mulaamasa/laamasa] – from the root to touch
أفضى [afda] – to come to, get to, reach
المسيس [al-masis] – from the root to touch
باء / باه / باءة [baa/bah/baa’a] – coitus
خالط / مخالطة [mukhaalata/khaalata] – associate with, mingle
مداعبة [mudaa’aba] – banter, foreplay; a preamble to sex
ملاعبة [mulaa’aba] –petting, teasing, foreplay; from the root to play
عمل قوم لوط / اللواط /اللواطة / اللوطية [‘aml qawm Lut/liwaat/liwaata/luwtiya] – “the acts of the people of Lot”, that is, homosexual activity, sexual perversion between two men
فاحشة [faahisha] – lewdness or vulgarity in general; distasteful or unlawful acts
زنا ، زنى [zina] – adultery
فسق [fisq] – to go astray; sexual immorality in general
عهارة [‘ahaara] – fornication
أهل [ahl] – household, people living together; almost always the women in particular:
إلى أهله كناية عن الجماع أي جماع حلاله زوجته أو أمته - المجالس الوعظية باب التسمية على كل حال وعند الوقاع “To his household” : allusion to sex, that is, lawful sex of a man with his wife or female servant – Al-Majalis Al-Wa’dhiya