Meaning: Natural relatives.
From Shakespeare's Hamlet
Biblical Meaning: The physical world of men.
Matthew 16:17
And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven.
John 1:13
Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of God.
Galatians 1:16
To reveal his Son in me, that I might preach him among the heathen; immediately I conferred not with flesh and blood:
Ephes. 6:12
For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.