FACT: Their original names were la Santa Clara, la Pinta, and la Santa Gallega.
As was common of the time, the crews gave each ship nicknames. La Santa Clara became la Niña ("the girl"); la Pinta became la Pintada ("the painted one," in other words, "the prostitute"); and la Santa Gallega became Maria Galante (the name of another prostitute). The church censored these nicknames, but the way we remember them today borrows heavily from the crews' vernacular.