Woman is a noun (used with a/an/the) and female is an adjective (which describes
a noun). So we say:
▶️ She is the country’s first female president.
woman president
▶️ The president of the country is a woman.
a female
There is a similar rule with male (adjective) and man (noun):
▶️ Male life expectancy is often lower than female life expectancy.
(male / female are adjectives describing the noun “life expectancy”)
▶️ Women live longer than men.
It is possible to use “female” and “male” as nouns, but this is usually only done when
talking about animals – or when writing scientific papers where humans are part of
the experiment:
▶️ The treatment was given to three males and three females between ages 40
and 45.
▶️ There are nine puppies available for adoption – seven males and two
females.
Masculine and feminine are also adjectives which describe things that are like
what people perceive to be typical of a man / typical of a woman.
▶️ Pink is considered a feminine color.
(women typically enjoy/wear pink; men typically do not)
▶️ American football is considered a masculine sport.
(men typically play/enjoy American football; women typically do not)