Historic seagoing member with a feminine name (6)

Here is my best explanation:

'historic seagoing' is the definition.
I can't judge whether this defines the answer.

'member with a feminine name' is the wordplay.
'member' becomes 'arm' (arm is a kind of member).
'with' says to put letters next to each other.
'a feminine name' becomes 'ada' (I am not sure about the 'feminine' bit.**).
'arm'+'ada'='ARMADA'

Can you help me to learn more?