a.

1. 多餘的，過剩的
   Skills which have been made redundant by technological advance.

   由於技術進步而變得多餘的技術。

2. 累贅的，冗長的
3. 【主英】（因人員過剩而）被解僱的，失業的[Z]

adj.

1. no longer needed or useful; superfluous.
   ▸(of words) able to be omitted without loss of meaning or function.
   ▸Engineering  (of a component) not strictly necessary but included in case another component fails.
2. Brit. (of a person) no longer employed because there is no more work available.