Rachel Jeantel, 19, acknowledged parts of her story changed over time, the Orlando Sentinel reported. She also admitted taking two years off her age early on.
George Zimmerman is charged with the second-degree murder of Martin, 17, who was returning to a relative's home in a gated community in Sanford when he was shot in 2011. Martin was unarmed, but Zimmerman says he fired in self-defense after the teenager jumped him.
Jeantel told defense lawyer Don West she did not give Martin's full description of Zimmerman -- "a creepy-ass cracker" -- when she was first questioned about the phone call because she did not want to hurt the teenager's mother. Sybrina Fulton was present while a lawyer representing her family asked Jeantel about the conversation.
When she left the stand, Jeantel was warned she remains under subpoena.
The next witness, Jennifer Lauer, was on the phone with 911 at the time of the shooting. Lauer said she called the emergency line after hearing "grunting" and "wrestling" noises outside.
Jurors also heard a tape of her 911 call.
Jeantel in her direct testimony Wednesday described what she heard of the confrontation between Zimmerman and Martin.