The Collaborative International Dictionary of English v.0.48:

Prudish \Prud"ish\, a.
   Like a prude; very formal, precise, or reserved; affectedly
   severe in virtue; as, a prudish woman; prudish manners.
   [1913 Webster]

         A formal lecture, spoke with prudish face. --Garrick.
   [1913 Webster]

WordNet (r) 3.0 (2006):

prudish
    adj 1: exaggeratedly proper; "my straitlaced Aunt Anna doesn't
           approve of my miniskirts" [syn: priggish, prim,
           prissy, prudish, puritanical, square-toed,
           straitlaced, strait-laced, straightlaced,
           straight-laced, tight-laced, victorian]