Boyd’s Bible Dictionary:
Morning star (2 Peter 1:19).
Concise Bible Dictionary:
The word is from θῶς and θέρω, “to bring light” (2 Pet. 1:19). Prophecy is a light in this dark world respecting things here and judgment. But, in contrast to judgment, the dawn and the day star are a better hope, not seen by those who appear only when the sun is risen, but for saints who look for Christ before He appears.