Sub test()
Dim Nom As String, Wsh As Worksheet, CelNom As Range
Nom = "NUNUCHE"
For Each Wsh In ThisWorkbook.Worksheets
Set CelNom = Wsh.Columns("A").Find(What:=Nom, LookIn:=xlValues, _
LookAt:=xlWhole, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
MatchCase:=False, SearchFormat:=False)
If Not CelNom Is Nothing Then CelNom.EntireRow.Delete
Next Wsh
End Sub