1.) One who is unaware of what it really means to be of a sexual orientation other than heterosexual.*
2.) One who does not understand LGBTQIA etc. history and/or culture.*
3.) One who holds one or more misconceptions about LGBTQIA etc. people.*
*This person may come off as homophobic by accident, but is not necessarily homophobic in actuality.
Sally seems homophobic, but she's really just homoignorant. She doesn't hate or dislike gay people, she just hasn't ever gotten to know someone who's gay, so she doesn't know that her words come out offensively.