Lewis & Short

arcŭātim, adv. [arcuo], in the form of a bow (perh. only in the foll. exs.): millepeda animal multis pedibus arcuatim repens, Plin. 29, 6, 39, § 136: sanguis arcuatim fluens, Fest. s. v. Tullios, p. 352 Müll.