treachery
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noun
(plural
treacheries
)
betrayal
of
trust
;
deceptive
action
or
nature
:
裏切り, 背信, 反逆.
e.g.
his resignation was perceived as an act of treachery
e.g.
the treachery of language.
ORIGIN
Middle English
: from
Old French
trecherie
, from
trechier
‘to
cheat
’.