Despite different etymologies estoner and entumir / estumir are semantically virtually indistinguishable, so that their orthographical similarity may well have led to confiusion of the different verbs.
v.a.
1to stun, daze:
(
s.xiii2/4; MS: s.xiii2
) Par ço fu Adam descunfit Quant li deables li out dit K’il serat si cum Dé, Par orguil ki l’ad entumé
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