Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
Cĕlĕres, um, = Κέλερες [cello, those who are prominent in position, = celsi; acc. to some from κελης, eques], the orig. general name for patricians or knights, Plin. 33, 2, 9, § 35; Paul. ex Fest. p. 42 (cf. Nieb. Röm. Gesch. 1, p. 367 sq.; O. Müll. Etrusk. 1, p. 382; and v. Trossuli and Flexuntes); in particular, the body-guard of the king, Liv. 1, 15, 8; 1, 59, 7; Dig. 1, 2, 2, § 15; cf. Serv. ad Verg. A. 11, 603, and Nieb. and Müll. above cited.
In sing.: Cĕler, ĕris, m., the chief of the Celeres, Ov. F. 4, 837; Paul. ex Fest. l. l.