Okay, I'm being a little sarcastic, but I cannot believe how easily people throw around the term phobia at the moment.
On FB I'm part of a cloth sanitary pad chat group (I realise how weird that sounds). Someone posted a link to 15 cartoons about periods "that only women will understand". The first comment is "this is transphobic". There is then a back and forth with one person accusing everyone else of transphobia. Someone has attempted to point out that it's not transphobic, however it could be argued that it has failed to take into account trans people, so admitting there's an issue, and has been told "you don't get to decide what's phobic, you're not part of the oppressed minority".
I'm pretty certain phobia has a specific meaning. And not including trans people isn't automatically transphobic. "15 things only straight women will understand" wouldn't be homophobic. It's just about straight women. It might display a lack of knowledge, but that's not the same as homophobia.
I have friends who won't identify as bisexual anymore (specifically, on the kink scene), because apparently the word bisexual is transphobic as it excludes trans people. Pansexual is what you have to be. Again, just because the word bisexual doesn't explicitly say "I'll sleep with trans people" that surely doesn't make it phobic? And since when is having sexual preference indicative of a phobia? Straight people are not homophobic because they don't want to have sex with people of the same sex. That's just their sexual preference.
I've put this in feminism chat because although asking about the meaning of a word isn't directly feminist, I am really annoyed that this has now reached the point where a support group for women asking all kinds of questions about periods, incontinence (often post childbirth) and advice for helping their teenage daughters, has suddenly become somewhere where you can be transphobic for saying that women have periods. although when I read the post I just laughed. Because, of course.