king--queen
lord--lady
wizard--witch
nephew--niece
ram--ewe
sir--madam
son--daughter
uncle--aunt
bull--cow
boar--sow

Girl originally meant a child of either sex, and was used for male
or female until about the fifteenth century.

Drake is peculiar in that it is formed from a corresponding feminine
which is no longer used. It is not connected historically with our
word _duck_, but is derived from _ened_ (duck) and an obsolete suffix
_rake_ (king). Three letters of _ened_ have fallen away, leaving our
word _drake_.

Gander and goose were originally from the same root word. _Goose_
has various cognate forms in the languages akin to English (German
_Gans_, Icelandic _gás_, Danish _gaas_, etc.). The masculine was
formed by adding _-a_, the old sign of the masculine. This _gansa_ was
modified into _gan-ra_, _gand-ra_, finally _gander_; the _d_ being
inserted to make pronunciation easy, as in many other words.

Mare, in Old English _mere_, had the masculine _mearh_ (horse), but
this has long been obsolete.