Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
circum-cingo, ĕre, v. a., to enclose around, surround: quā Mons Apenninus regiones Italiae Etruriaeque circumcingit, Vitr. 2, 6, 5: eum zonā gloriae, Vulg. Ecclus. 45, 9: PORTICVS, Inscr. Orell. 4043.
In part. pres., Cels. 7, 15: telis circumcingentibus, Sil. 10, 2.