The ranges are "more or less" defined. It is the natural range of a singer. Defining as bass, tenor, etc. is usual. Any particular singer may vary in his/her natural range.

A tenor ranges from the octave below middle C to the A above it; or more broadly, the adult male voice between the bass and the alto or counter-tenor.
Bass- voice ranging from Eb below the bass stave to the F above it.

The female voice may be characterized similarly. I remember Yma Sumac who could range all over the place.