Sex Definition and Types: What Is Sex Exactly?

    Updated 03 February 2023 |
    Published 07 April 2020
    Fact Checked
    Reviewed by Olga Adereyko, MD, Primary Care Physician, General Practitioner, Medical Consultant
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    In general, sex is thought to be penetrative intercourse between a man and a woman. But depending on your sexual orientation and personal definition of sex, that’s not necessarily the case. Let’s take a closer look at what is considered sex. 

    Sex definition

    What does sex mean? Well, the most commonly accepted sex definition refers to vaginal intercourse. The dictionary defines intercourse as penetration of a woman’s vagina by a man’s penis (also known as coitus). In contrast, other forms of penetration, like anal or oral, do not involve intercourse.

    That being said, the dictionary’s conventional sex meaning doesn’t come close to covering the wide range of sexual activities people engage in. Other forms of physical intimacy fall under the umbrella of sex, from making out to intercourse with multiple partners. 

    Any way you look at it, though, all sexual acts should be comfortable, enjoyable, and fully consensual for everyone concerned.

    Types of sex

    Sex may be divided into three main categories: vaginal, anal, and oral (i.e., either fellatio or cunnilingus). Most can agree they all count as sex, despite the fact that oral sex sometimes hovers in a gray area. Besides the above, what is considered sex? 

    There’s manual stimulation of the genitals (e.g., hand jobs or fingering), cybersex, in which partners trade suggestive messages, photos, or videos while masturbating. Some might even consider solo masturbation as sex.

    The varying definitions of sex are fairly broad and for those who favor unusual practices or having multiple partners, the definition of sex is even broader. For example, certain fetishes or kinks could be thought of as sex, although none of the traditional sex acts are involved.

    Definition of sexual activity

    Did you know that the definition of sexual activity can include doing things that are intended to attract or elicit sexual desire in another person? This might mean flirting, dirty dancing, or simply sending risqué texts and photos.

    Sexual activity has many complicated aspects and encompasses behavior of all kinds. It serves to highlight humans’ basic biological need to reproduce as well as a sense of urgency to engage in physical pleasure. There are also bonding and emotional aspects to sexual activity, such as forming a stronger psychological connection or consummating a marriage. 

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    List of sexual activities

    Now it’s time to get down to the nitty-gritty! Below, Flo’s compiled a list of sexual activities, ranging from PG-rated to the naughtiest of the naughty. Note, it’s completely normal to feel like some of the options below aren’t for you. 

    And remember, if you’re trying something new, be honest with your partner (or partners) about your comfort level. Make sure you trust them to stop if you change your mind or suddenly feel uneasy. The best sex is the kind that both you and your partner(s) fully enjoy.

    • Sexual intercourse (or PIV)

    It’s traditional sex between a man and a woman, where the penis penetrates the vagina. Slightly more adventurous positions tend to offer added stimulation for your clitoris, producing an orgasm. Just keep in mind that it may result in pregnancy if you don’t take the proper precautions.

    When a man penetrates his male or female partner’s anus with his penis. 

    • Oral sex (cunnilingus)

    It describes using the lips, tongue, and fingers to stimulate female genitals. This could involve licking and sucking on the clitoris, inserting the tongue or fingers into the vagina, or both. 

    • Oral sex (fellatio)

    Inversely, this refers to using the lips, tongue, and hands to stimulate male genitals. It includes licking and sucking on the penis, perhaps accompanied by penis stroking or cupping of the testicles.

    • Manual stimulation (hand jobs)

    Stroking the male penis with the hands.

    • Manual stimulation (fingering)

    Stimulating the clitoris and vagina, either by stroking or inserting one or more fingers into the vagina.

    • Masturbation

    It’s a type of self-stimulation which, for women, might entail the use of hands, fingers, and sex toys like a vibrator to penetrate the vagina. Masturbation could also allow you to better direct your partner on how to pleasure you in the future. For men, however, self-stimulation typically involves stroking the penis with their hands and fingers.

    • Mutual masturbation

    Also known as cybersex, both partners self-stimulate over the phone, via text, or by sending photos and videos. 

    • Sexting

    Similarly, this includes sending nude or mostly nude photos and videos, as well as text messages about desired sexual acts. It may or may not involve one or both partners masturbating.

    • Ménage a trois

    Sex between three individuals (of any combination of genders), which is usually referred to as a “threesome.” Acronyms like MMF or MFF will indicate which genders are participating. Note that sexual intercourse doesn’t have to occur between all parties. For example, one or both partners in a relationship might wish to kiss or touch a new, third partner but neither wants to have intercourse with them. If you’re in a committed relationship, set a few ground rules first regarding what’s off-limits.

    • Kissing/making out

    Kissing might happen on its own, or in combination with touching your partner (either over or under their clothes).

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    Sex should always be safe and enjoyable for everyone involved, and it’s extremely important to protect yourself against unwanted pregnancy and sexually transmitted diseases. No matter what your definition of sex is, sexual experiences are as unique and creative as the people who engage in them. There’s never a wrong way to have sex as long as it’s consensual. 

    History of updates

    Current version (03 February 2023)

    Reviewed by Olga Adereyko, MD, Primary Care Physician, General Practitioner, Medical Consultant

    Published (07 April 2020)

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