nodular

noun

1. a small knot or irregular, rounded lump
2. Anat. a small node
3. Bot. a small knot or joint on a stem or root, esp. one containing nitrogen-fixing bacteria
4. Geol.
   1. a small, hard lump or mass of a mineral or rock that is embedded in a larger rock
   2. a usually small, roundish lump or mass of manganese, cobalt, etc. found on the floor of the sea or large lake

Origin: L nodulus, dim. of nodus, a knot: see net