The passage below is from the catholic website. After you have read through it, I will list verses where you will find the word saint used in the Bible and some of the differences

"How does the Church choose saints?

Canonization, the process the Church uses to name a saint, has only been used since the tenth century. For hundreds of years, starting with the first martyrs of the Church, saints were chosen by public acclaim. Though this was a more democratic way to recognize saints, some saints' stories were distorted by legend and some never existed. Gradually, the bishops and finally the Vatican took over authority for approving saints.

In 1983, Pope John Paul II made sweeping changes in the canonization procedure. The process begins after the death of a Catholic whom people regard as holy. Often, the process starts many years after death in order give perspective on the candidate. The local bishop investigates the candidate's life and writings for heroic virtue (or martyrdom) and orthodoxy of doctrine. Then a panel of theologians at the Vatican evaluates the candidate. After approval by the panel and cardinals of the Congregation for the Causes of Saints, the pope proclaims the candidate "venerable."

The next step, beatification, requires evidence of one miracle (except in the case of martyrs). Since miracles are considered proof that the person is in heaven and can intercede for us, the miracle must take place after the candidate's death and as a result of a specific petition to the candidate. When the pope proclaims the candidate beatified or "blessed," the person can be venerated by a particular region or group of people with whom the person holds special importance.

Only after one more miracle will the pope canonize the saint (this includes martyrs as well). The title of saint tells us that the person lived a holy life, is in heaven, and is to be honored by the universal Church. Canonization does not "make" a person a saint; it recognizes what God has already done.

Though canonization is infallible and irrevocable, it takes a long time and a lot of effort. So while every person who is canonized is a saint, not every holy person has been canonized. You have probably known many "saints" in your life, and you are called by God to be one yourself.

When did the Church start honoring saints?

By the year 100 A.D., Christians were honoring other Christians who had died, and asking for their intercession. Many people think that honoring saints was something the Church set up later, but it was part of Christianity from the very beginning. As a matter of fact, this practice came from a long-standing tradition in the Jewish faith of honoring prophets and holy people with shrines. The first saints were martyrs, people who had given up their lives for the Faith in the persecution of Christians."

Quotes to consider: Psalm 106:16 Here Aaron is called a saint (the NIV uses the word consecrated).

Psalm 148:14 The saints in this verse are the children of Israel.

Romans 1:7 The letter to the Romans is written to 'all in Rome, called to be saints'.

Phillipians 4:21 'Salute every saint' is the instruction or greeting given.

As we read these and the many other verses we find that these people were called saints WHILE THEY WERE ALIVE not after they died. They did not have to perform miracles, or be martyrs. They did have to KNOW and BELIEVE God.

Another big difference is that we don't find any reference to being able to pray to saints to intercede for us. The Bible tells us (1 Timothy 2:5) that there is only one mediator between us and God and that is Jesus.