shudder (v.) Look up shudder at Dictionary.com
early 14c., possibly from Middle Dutch schuderen "to shudder," or Middle Low German schoderen, both frequentative forms from Proto-Germanic *skuth- "to shake." Related: Shuddered; shuddering.
shudder (n.) Look up shudder at Dictionary.com
c.1600, from shudder (v.).