- pith - soft spongelike central cylinder of the stems of most flowering plants
--1 is a kind of plant tissue
--1 has substance: parenchyma- kernel, substance, core, center, essence, gist, heart, heart and soul, inwardness, marrow, meat, nub, pith, sum, nitty-gritty - the choicest or most essential or most vital part of some idea or experience; "the gist of the prosecutor's argument"; "the heart and soul of the Republican Party"; "the nub of the story"
--2 is a kind of content, cognitive content, mental object
--2 has particulars:bare bones; hypostasis; quiddity, haecceity; quintessence; stuff - kernel, substance, core, center, essence, gist, heart, heart and soul, inwardness, marrow, meat, nub, pith, sum, nitty-gritty - the choicest or most essential or most vital part of some idea or experience; "the gist of the prosecutor's argument"; "the heart and soul of the Republican Party"; "the nub of the story"