The word "爸妈" is formed by combining the character for father, "爸" (bà), and the character for mother, "妈" (mā), into a single compound word. This juxtaposition directly merges the two individual meanings to create a new term that collectively refers to both parents, meaning "mom and dad" or "parents". Each character contributes its specific semantic value to the whole without alteration, resulting in a straightforward lexical unit that denotes the dual concept.