Definify.com
Webster 1913 Edition
Phosphor
1.
Phosphorus.
[Obs.]
Addison.
2.
The planet Venus, when appearing as the morning star; Lucifer.
[Poetic and Rare]
Pope.
Tennyson.
Webster 1828 Edition
Phosphor
PHOS'PHOR
,Noun.
The morning star or Lucifer; Venus, when it precedes the sun and shines in the morning. In this sense, it is also written Phosphorus.