ETYMOLOGY
from lean (adj.) + witted (having wit)
EXAMPLE
“… A lunatike leane-witted foole,
Presuming on an agues priuiledge,
Darest with thy frozen admonition
Make pale our cheeke, chasing the royall bloud
With furie from his natiue residence.
Now by my seates right royall maiestie,
Wert thou not brother to great Edwards sonne,
This tong that runnes so roundly in thy head,
Should runne thy head from thy vnreuerent shoulders. …”
From: The Tragedie of King Richard the Second
1st Quarto
By William Shakespeare, 1597
Lexicophilia 