The form planet2 is a cross reference to the following entry:
The TLF indicates that the earliest attestation of this word in 1119 comes from Comput ants 2800. However, that citation attests to the use of the Latin word in an Anglo-Norman context: ‘Des esteiles reials Que apellum ‘principals’, Que en latin numuns 'Planetes' par raisuns’
[hp]