Being in the centre; central.
Pertaining to a nerve centre.
Being a member of the subclass Coscinodiscophyceae (corresponding to the Centrales.)
Related to a foundation. base, or basis; serving as a foundation.
essential; extremely important
The lowest frequency of a periodic waveform.
A main or major principle, rule, law, etc. which serves as the foundation or basis of a system; an essential part
The lowest partial of a complex tone.