The livery of someone such as a soldier or servant is the special uniform that he or she wears.
(士兵或仆人的)制服 ...attendants in red and black livery. ...穿红黑制服的随从们。
The horses were post; and neither the carriage, nor the livery of the servant who preceded it, were familiar to them.
马是驿站上的马,至于马车本身,车前待从所穿的号服,他们也不熟悉。