2. (Mus.) Same as Contra. Formerly used to designate any under part which served for contrast to a principal part, but now used as equivalent to counter tenor.

3. (Far.) The breast, or that part of a horse between the shoulders and under the neck.

4. The back leather or heel part of a boot.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Counter tenor \Coun"ter ten`or\ (t?n`?r). [OF. contreteneur. Cf. Contratenor, and see Tenor a part in music.]

(Mus.) One of the middle parts in music, between the tenor and the treble; high tenor.

Counter-tenor clef (Mus.), the C clef when placed on the third line; -- also called alto clef.

Source: Webster's Revised Unabridged Dictionary (1913)