Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
‡ summārĭum, ĭi, n. [summa], a summary, epitome, abstract: oratio, quae nunc vulgo breviarium dicitur, olim, cum Latine loqueremur, summarium, vocabatur, Sen. Ep. 39, 1.