forming a necessary base or core; of central importance
the lowest note of a chord in its original (uninverted) form
the tone that represents the fundamental frequency of a vibrating object such as a string or bell
one of a set of unrelated units of measurement, which are arbitrarily defined and from which other units are derived. For example, in the SI system the fundamental units are the meter, kilogram, and second
the lowest frequency produced by the oscillation of the whole of an object, as distinct from the harmonics of higher frequency
another term for elementary particle.