"wish-wash", sense 2, 1697; antedates OED2 1842--

[Joel S. Berson]

"What the Council of Trade have sent you further about the West
Indies is but 'wishewashes' and nothing to your purpose."

1697 July 25.  Letter, William Blathwayt to Matthew Prior.  _Calendar
of the Manuscripts of the Marquis of Bath Preserved at Longleat,
Wiltshire_.  Historical Manuscripts Commission.  Printed for HM
Stationery Office, 1908.  Vol. III (Prior Papers), p. 140.

Antedates OED2 "wish-wash, n.", sense 2. fig., 1842--.

"wishy-washy", adj., goes back to 1693 in its sense (2.b.) most
closely related to this quotation.

Joel

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