Note: the noun is in the Middle English form 'BLONDERE' only
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for noun: from bland (vb.) to soothe, flatter + -er
1340 - Ayenbite - see Example below
From: Dan Michel's Ayenbite of Inwyt, Or, Remorse of Conscience:
In the Kentish Dialect 1340 A.D.
Edited from the MS. by Richard Morris, 1866