What is "to breathe a vein"

Breathe \Breathe\, v. t.

1. To inhale and exhale in the process of respiration; to respire.

   To view the light of heaven, and breathe the vital air.
   --Dryden.

2. To inject by breathing; to infuse; -- with into.

   Able to breathe life into a stone.
   --Shak.

   And the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life.
   --Gen. ii. 7.

3. To emit or utter by the breath; to utter softly; to whisper; as, to breathe a vow.

   He softly breathed thy name.
   --Dryden.

   Or let the church, our mother, breathe her curse, A mother's curse, on her revolting son.
   --Shak.

4. To exhale; to emit, as breath; as, the flowers breathe odors or perfumes.

5. To express; to manifest; to give forth.

   Others articles breathe the same severe spirit.
   --Milner.

6. To act upon by the breath; to cause to sound by breathing. ``They breathe the flute.''
   --Prior.

7. To promote free respiration in; to exercise.

   And every man should beat thee. I think thou wast created for men to breathe themselves upon thee.
   --Shak.

8. To suffer to take breath, or recover the natural breathing; to rest; as, to breathe a horse.

   A moment breathed his panting steed.
   --Sir W. Scott.

9. To put out of breath; to exhaust.

   Mr. Tulkinghorn arrives in his turret room, a little breathed by the journey up.
   --Dickens.

10. (Phonetics) To utter without vocality, as the nonvocal consonants.

    The same sound may be pronounces either breathed, voiced, or whispered.
    --H. Sweet.

    Breathed elements, being already voiceless, remain unchanged

    Note: [in whispering].
    --H. Sweet.

    To breathe again, to take breath; to feel a sense of relief, as from danger, responsibility, or press of business.

    To breathe one's last, to die; to expire.

    To breathe a vein, to open a vein; to let blood.
    --Dryden.