Complex trauma (also known as complex PTSD) is a broad term that refers to repeated wounding within the context of a relationship.
A few examples that come to mind for me: childhood or adult sexual, physical, or emotional abuse (including neglect); surviving domestic violence; religious or spiritual abuse; having a partner or caregiver with narcissistic tendencies; and growing up with a parent or caregiver who was unpredictable and/or unable to meet your physical or emotional needs.
I think it’s also important to note the additional layer of relational wounding that often happens to people who are part of marginalized groups (BIPOC, LGBTQ+ folks, people who exist in larger bodies, disabled folks, neurodivergent folks, etc).
Trauma work should be done slowly, with a lot of care and focus on building safety, trust, and self-empowerment. What we know from an ever-growing body of research is that trauma is held not just in our minds, but in our bodies too. This means that effective healing from trauma includes a focus on somatic healing- developing an embodied sense of safety and healing the mind-body connection.