Bluer

adjective

1. Of the colour blue.

   "the deep blue sea"

2. Depressed, melancholic, sad.
3. Pale, without redness or glare; said of a flame.

   "The candle burns blue."

4. Supportive of, run by (a member of), pertaining to, or dominated by a political party represented by the colour blue.
5. Of the higher-frequency region of the part of the electromagnetic spectrum which is relevant in the specific observation.