Is gender determined by physical characteristics, inner feelings, or both? How you answer that question likely influences how you see and use this word "transgender."
Most progressives see transgender as a normal, value-neutral variation like skin color or height. From this perspective, transgender men (female body parts, but inner identification with masculinity) and transgender women (male body parts, but inner identification with femininity) ought to be openly accepted with this as their core identity. They call for empathy for having a gender identity or expression differing from the sex that was determined or assigned at birth, and support for hormone replacement therapy, sexual reassignment surgery, and other strategies to reduce discomfort and align bodies more closely with a person's gender identity. Many also celebrate the idea of transgender identity, and say it helps to break down traditional ideas of gender that they say have oppressed and restricted millions throughout history.
In contrast, many conservatives believe internal feelings and experiences do not determine gender, and that physical factors ought to be given more weight. They argue that biology is intricately linked to or determines gender, and that there are only two genders. They believe discomfort is healed when the mind is brought into alignment with the body, not the body into alignment with the mind. Some highlight Scriptural teachings on gender, with many religious conservatives seeing transgender identity as a violation of two divinely ordained genders in the Bible: male and female. From this perspective, surgical interventions to change the body are aggressive, invasive, harmful, and abusive when allowed for children. Some see transgender identity as a psychological disorder, as the American Psychological Association did until 2012.
People with the first perspective hold a broader view of gender (not confined to the body) and see it as helpful to a subset of vulnerable people with transgender feelings. They believe this view is effective in promoting greater public acceptance of transgender people, which will reduce discomfort in trans people. They see transgender identity as a real lived experienced, something that is inborn and natural. On the other side, there is concern from people who hold a second perspective — that gender is intricately linked to biological sex and not an identity. They see transgenderism as an ideology that is spread via peer contagion, advertising, or propaganda — not something that is natural or inborn. While they agree that there may be men who are more feminine and women who are more masculine, they believe people are happier and healthier when they accept their biological sex and embody it, and argue that teaching a broader definition of gender confuses and harms youth at a time that is already confusing (puberty), while potentially encouraging permanent social or physical changes when kids are still developing and learning about being male or female.
Supporters of the broader definition believe the benefits of helping transgender people to better understand themselves outweighs any risks. Meanwhile, opponents point to examples of risks, like de-transitioners (people who transitioned their gender, usually with medical treatment at a young age, then later regretted it, often with permanent and irreversible physical changes). They also point to what they see as potential harmful overreach, such as a boy who enjoys something considered by his peers to be “girlish" — such as fashion, dancing or even being more empathetic to someone — and adults convincing him he "really is" female and should identify or try to live that way.
People with the broader view of gender will typically refer to medical treatment for transgender people as "gender-affirming care" or "gender-confirming treatment"; people who see these treatments as harmful may call them simply "gender transition procedures."