Misbegotten means badly conceived, or born out of wedlock. A misbegotten scheme, misbegotten from the start, some misbegotten idea.
The old sense about birth is offensive and dead, and everything now goes on the figurative one — a misbegotten plan was wrong from the moment it was thought of, not merely badly executed. The mis- means wrongly and begotten is the old past participle of beget.
1adjectivemisbegottenBadly conceived from the start.
“The misbegotten plan to build a motorway through the park was finally dropped.”
misbegotten is a quality of fault.
From mis- + begotten.
Etymology from Wiktionary, CC BY-SA
Practised in A Song of Ice and Fire