inadvertence
[ C ]
an action or event that is unintentional:
Most people know that life, like history, is made up of inadvertencies.
There are quite a few typographical errors and inadvertencies.
It happened, however, through inadvertency.
Her exclamations and confessions seemed filled with inadvertencies.

SMART Vocabulary: related words and phrases

Not expected or planned
abrupt end
abrupt halt
abruptly
abruptness
ad hoc
inadvertence
inadvertent
inadvertently
inconceivable
inconceivably
sine die
spirit
spontaneity
spontaneous
spontaneously
unsuspected
untimely
untoward
unwilled
unwitting

Related word