Definify.com
Webster 1913 Edition
Breasthook
Breast′hookˊ
,Noun.
 (Naut.) 
A thick piece of timber in the form of a knee, placed across the stem of a ship to strengthen the fore part and unite the bows on each side. 
Totten.
 Webster 1828 Edition
Breasthook
BREAST'HOOK
,Noun.