Referencing the 7th century poet Sappho, the word sapphic is an umbrella term for women who are attracted to or have romantic relationships with other women, including both lesbian and bisexual women. This is distinct from the word lesbian, which refers to exclusive attraction to other women, and refers to the Greek island Lesbos where Sappho was born.
Below is a fragment of a love poem she wrote:
Beyond all hope, I prayed those timeless days we spent might be made twice as long. I prayed one word: I want. Someone, I tell you, will remember us, even in another time.