(of a diatom) bilaterally symmetrical.Compare with centric
- ‘Both articulated and broken pennate diatoms, up to 12 m long and 4 m wide, are scattered throughout the stromatolitic sinters.’
- ‘The major source of the spring diatom pulse was Skeletonema potamos and a variety of centric and pennate diatoms.’
- ‘At the shallow south end of the lake, most of the samples were relatively similar, dominated by pennate forms.’
- ‘Diatoms are photosynthetic protists, which are classified into centric and pennate diatoms, according to whether they have a radial or bilateral symmetry.’
- ‘Tissue-level concentrations of hydrophilic and lipophilic extracts caused high levels of mortality in a sympatric pennate diatom.’
Mid 19th century: from Latin pennatus feathered, winged, from penna feather.