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Sexual Fluidity Vs Sexual Orientation

What’s the Difference Between Sexual Fluidity and Sexual Orientation?
4 Min Read
Sexual Fluidity Vs Sexual Orientation
The past few decades have been marked by increasing awareness of the fact that sexuality and gender aren’t binary — in other words, there aren’t simply two options. When it comes to sexuality, it used to be that people could either identify as heterosexual or homosexual — and the latter was seen as a “deviation” from social norms.

Heterosexuality may still be the assumed default, but people are using words including pansexual, asexual, bisexual, and queer to identify themselves and express their sexual truths. Similarly, people are finding plenty of words to explain their gender beyond the assumed default of cisgender, such as being transgender, nonbinary, or agender.

The relatively novel (but still limited) freedom to express and celebrate sexual orientation has been a major success of the LQBTQ+ movement. And with all of the new words to express yourself, it can feel confusing if you’re trying to understand your own sexual identity. Is there room for exploration, or should you simply know? In other words — what’s the difference between sexual fluidity and sexual orientation?The answer isn’t necessarily straightforward or simple.

Key Definitions

Sexual orientation is heavily influenced by biology — so no, people don’t simply “choose” to be members of the LGBTQ+ community. Have you heard of the “gay gene” (or, rather, gay genes)? A number of different traceable factors, including the types/quantities of hormones you are exposed to in-utero, may help determine which gender(s) you find yourself attracted to later in life (for more on this, read Tell Me What You Want by Justin Lehmiller) (1).

Sexual fluidity (also known as sexual flexibility), on the other hand, is how likely you are to deviate from your set preference for whatever reason. For example, people with low levels of sexual fluidity will most likely consistently choose the same type of partners. Conversely, someone with high levels of sexual fluidity could identify as heterosexual, but frequently express themselves sexually in other ways (1). They may also be more likely to try new things within their relationships, or have non-conforming sexual fantasies

Determinations of Sexual Fluidity

What factors influence your level of sexual fluidity?

Interestingly, if you identify as a straight woman, you are more likely to be sexually flexible than a straight man. Straight women are more likely to fantasize about scenarios that do not align with their sexual orientation, and are more physically responsive to a wide range of stimuli than their heterosexual male counterparts (1).

The book Sex at Dawn by Cacilda Jethá and Christopher Ryan describes an experiment where a group of men and women, of a range of sexual identities, were shown sexual stimuli while the experimenters monitored their physical reactions. Unlike the gay and straight men or lesbian women, who all responded according to their orientation, heterosexual women responded to almost all sexual stimuli, even when it contradicted their self-reported sexual orientation. Interestingly, women were more likely than men to lie about experiencing arousal (a trend which can likely be attributed to the dismissal of female sexuality by Western culture).

This trend might have an evolutionary explanation. While preferring a male partner was once a prerequisite for female reproduction, historical risks once meant that partner could be compromised during activities such as hunting or defending the community. In such instances, relying on another partner — be that a man or a woman — would be a key part of helping a woman make sure her children survived.

How do you know if you are sexually fluid, or that your sexual orientation has shifted?

There’s no hard-and-fast rule when it comes to defining your own sexuality. Being sexually fluid and being pansexual, for example, can look the same from the outside — what matters is how you define and express yourself.

Ultimately, it comes down to what feels natural to you versus what feels circumstantial or experimental. In a 2016 paper, psychologist Lisa Diamond explained that bisexuality is a “stable sexual predisposition,” while sexual fluidity refers to someone’s response to erotic stimuli. “Although both bisexuality and sexual fluidity can produce nonexclusive sexual attractions, such attractions are expected to be a regular feature in the lives of bisexually oriented individuals, whereas they may prove more sporadic and/or context-specific for individuals who are highly sexually fluid,” she said.

It may take several experiences to understand whether you are discovering a new facet of your own sexuality or simply exercising fluidity. Ultimately, these definitions should help your own understanding of yourself, and you should feel empowered to take all the time you want without judgment. It’s alright to not have it all figured out — in fact, being uncertain means you are invested in the journey of sexual self-discovery.


  1. Lehmiller, Justin J. Tell me what you want: The science of sexual desire and how it can help you improve your sex life. Hachette UK, 2018.
  2. Ryan, Christopher, et al. Sex at dawn: How we mate, why we stray, and what it means for modern relationships. New York: Harper Perennial, 2011. 
  3. Diamond, Lisa M. "Sexual fluidity in male and females." Current Sexual Health Reports 8.4 (2016): 249-256.


  1. @shannontomasik