The Collaborative International Dictionary of English v.0.48:
Stud-horse \Stud"-horse`\, n. [AS. st[=o]d-hors.] A stallion, esp. one kept for breeding. [1913 Webster]WordNet (r) 3.0 (2006):
studhorse n 1: adult male horse kept for breeding [syn: stud, studhorse]