Shaver, Schouwer, Schaefer, Sheffer Surnames and Variants

Shaver
Americanized form of Dutch Schouwer, an occupational name for an inspector of market weights and measures, Dutch schouwer ‘inspector’.
Altered form of German Schaefer.

Dictionary of American Family Names, Oxford University Press, ISBN 0-19-508137-4

Schaefer
German (Schäfer) and Jewish (Ashkenazic): occupational name for a shepherd, from an agent derivative of German Schaf, Middle High German schaf ‘sheep’. This name is widespread throughout central and eastern Europe.

Dictionary of American Family Names, Oxford University Press, ISBN 0-19-508137-4