名詞 rubber stamp:

1. a stamp (usually made of rubber) for imprinting a mark or design by hand
   同義詞：handstamp
2. routine authorization of an action without questions

動詞 rubber stamp:

1. stamp with a rubber stamp, usually an indication of official approval on a document
   同義詞：rubberstamp, handstamp
2. approve automatically
   同義詞：rubberstamp