in Queer contexts, the spectrum refers to the wide variety of identities that fall between two binary or “extreme” points.

An example would be the sexuality spectrum (as exampled by the Kinsey scale), with homosexual on one end, heterosexual on the other, and bisexual+ identities falling somewhere in between (and asexual identities, in this respect, being off the spectrum).

In the gender spectrum, one might look at female and male being at either end, with nonbinary identities falling in between (and agender being off the spectrum). Trans men and trans women may see themselves as being on either end of that spectrum.

Another example is the asexual spectrum, which covers the wide variety of asexual identities within it; one “extreme” point at one end may be asexuality/aromanticism, on the other, allosexual.

It is important to note, however, that the term spectrum on its own – particularly, when used in the context as being “on the spectrum” – has become synonymous with the autistim spectrum.