Hearken and hear this, O house of Jacob, who are called by the name of Israel, and are come forth out of the waters of Judah, or out of the waters of baptism, who swear by the name of the Lord, and make mention of the God of Israel, yet they swear not in truth nor in righteousness.  1 Nephi 20:1

The word "baptisma" is derived from a Latin and Greek word meaning "washing."

The practice of ritualistic washing occurred when one wanted to purify him/herself before entering the temple.  That was an Old Testament practice but never called baptism.

In the Bible, the word only appears in the New Testament, starting with Jesus being baptized by John the Baptist. The time frame would be 30 AD.  That's when baptism became a public profession of an internal decision, for example, to live a more Godly life or to follow Christ.

Around the time that Nephi wrote the above statement (apparently 600 BC), the Greek language had not spread to Israel until the Greeks invaded in 312 BC.  Jews spoke Hebrew.  They would not have known the word "baptism" as Nephi used the word.