countersign
1. [ noun ] a secret word or phrase known only to a restricted group
Synonyms: word watchword parole password
Examples:

"he forgot the password"

Related terms: positive_identification secret
2. [ verb ] add one's signature to after another's to attest authenticity
Examples:

"You must countersign on this line of the contract"

Related terms: sign countersignature
3. [ noun ] a second confirming signature endorsing a document already signed
Synonyms: countersignature
Related terms: signature
Similar spelling:   countersink
  counterstain
  counterperson
  counterspy
  counterman
  countervailing
  Conteras
  countermand
  counterpane
  countersuit
  counterplan
  countershot
  countermine
  counteroffer
  counterpoint
  Contreras
  counterwoman
  counterpunch
  countertenor
  countercharge
  counterfeiter
  counterstrike
  counteraction
  counterchange
  counterweight
  counterpoison
  countertop
  counteract
  countercurrent
  counterbalance
  countermove
  counterplay
  counterglow
  counterfoil
  counterfire
  counterplea
  counterfeit
  counterplot
  countercoup
  counterpose
  countervail
  counterbore
  counterblow
  counterpart
  counter_tube
  conterminous
  controversial
  countermarch
  counterblast
  countercheck
  counterclaim
  counterpoise
  counteractive
  counter-drill
  counter_check
  countermelody
  contrite
  counterpoised
  counterattack
  commuter