The Collaborative International Dictionary of English v.0.48:

Henry \Hen"ry\, n.; pl. Henrys. [From Joseph Henry, an
   American physicist.]
   The unit of electric induction; the induction in a circuit
   when the electro-motive force induced in this circuit is one
   volt, while the inducing current varies at the rate of one
   amp[`e]re a second.
   [1913 Webster]

WordNet (r) 3.0 (2006):

henry
    n 1: a unit of inductance in which an induced electromotive
         force of one volt is produced when the current is varied at
         the rate of one ampere per second [syn: henry, H]
    2: English chemist who studied the quantities of gas absorbed by
       water at different temperatures and under different pressures
       (1775-1836) [syn: Henry, William Henry]
    3: a leader of the American Revolution and a famous orator who
       spoke out against British rule of the American colonies
       (1736-1799) [syn: Henry, Patrick Henry]
    4: United States physicist who studied electromagnetic phenomena
       (1791-1878) [syn: Henry, Joseph Henry]

The Free On-line Dictionary of Computing (19 January 2023):

henry

    (H) The SI unit of inductance: one henry is the
   inductance of a closed loop in which the induced voltage is
   one volt if the current flowing through it changes by one
   ampere each second, i.e., 1 H = 1 Vs/A.  Named after the
   American physicist Joseph Henry (1797-1878).

   (1997-03-16)