bosom
The chest, usually used in reference to women.
crown
A former denomination of British coinage equivalent to 1/4 pound, 5 shillings, or 60 (old) pence.
fancy
Housman uses fancy to mean affection or romantic interest.
guinea
A former denomination of British coinage roughly equivalent to one pound.
in vain
without success or result
pound
A basic denomination of British coinage still used today.
rue
bitterly regret (something one has done or allowed to happen) and wish it undone