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countersign

1 ENTRIES FOUND:
countersign /ˈkaʊntɚˌsaɪn/ verb
countersigns; countersigned; countersigning
countersign
/ˈkaʊntɚˌsaɪn/
verb
countersigns; countersigned; countersigning
Britannica Dictionary definition of COUNTERSIGN
[+ object]
: to sign (a document) after another person has already signed it especially to show that it is valid or authentic