Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
†† Sĕrăphīn or Sĕrăphīm, plur. indecl., = [??], the Seraphim, a higher order of angels among the Hebrews, Vulg. Isa. 6, 2; Prud. Cath. 4, 5; Isid. Orig. 7, 5, 24 sq.