Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
cŏ-haeresco (-hēresco), si, 3, v. inch. n. [cohaereo], to hang together, cohere (very rare): atomi cohaerescunt inter se, Cic. N. D. 1, 20, 54; id. Fin. 1, 6, 17: pituita in gulā cohaerescens, Plin. 24, 15, 80, § 130; 20, 16, 64, § 172.