Something that is otiose is unnecessary, worthless, ineffective, or impractical; an otiose person is lazy and thus ineffective.
When you negotiate with another person, you are trying to reach an agreement of some kind; you are usually doing business or trying to solve a problem.
capable of being passed or negotiated
a discussion intended to produce an agreement
someone who negotiates (confers with others in order to reach a settlement)
not capable of being passed or negotiated
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