佬 is a colloquial suffix for 'person/guy,' common in Cantonese-influenced Mandarin. 大佬 = big boss, 阔佬 = rich person, 肥佬 = fat guy. It can be neutral or mildly derogatory depending on context.
Left person radical — the side-form of 人. Marks 佬 as a noun for a particular kind of person, fellow, or guy. Same radical anchors most of the human-noun and human-action vocabulary: 你 you, 他 he, 们 plural marker, 住 to dwell, 信 trust.
Right side 老 supplies the sound — lǎo exact match. The 'old' meaning of 老 leaves a faint semantic echo: 佬 began in southern Chinese as a respectful 'old fellow' term before drifting into today's casual '-guy' suffix (大佬 boss, 阔佬 rich guy, 乡巴佬 country bumpkin).
