Pop star Taylor Swift has filed an application to trademark the title of her unpublished novel.

The Love Story singer filed trademark applications in January (15) to stop lyrics from her hits Blank Space and Shake It Off being used on unofficial products and merchandise.

She registered more requests with the U.S. Patent and Trademark Office on 3 December (15), including the phrase A Girl Named Girl, the title of a novel she wrote when she was 14 years old, but it is not known if Taylor is planning to publish the book.

Taylor is also attempting to trademark "Swiftmas", a word used by her fans when the pop star surprises them with gifts, the song title "Blank Space" and the track's lyric, "And I'll write your name".

She has also filed a petition to trademark the date "1989", the name of her latest album, but only if it is presented in its "stylised form".

In January (15), she trademarked lyrics including, "This sick beat" from Shake It Off, "Could show you incredible things" and "Nice to meet you, where you been?" from Blank Space, as well as "Cause we never go out of style" from her single Style.

The singer's 1989 World Tour has been running since May (15), but the trek comes to a close in Melbourne, Australia on Saturday (12Dec15), a day before her 26th birthday on 13 December (15).

Taylor recently denied reports she is planning to throw a large party to celebrate both her birthday and the end of the tour.

In an Instagram.com message aimed at Australian reporters, she wrote, "Aussie press, I love your enthusiasm but my birthday isn't for 2 weeks and it'll be a quiet one this year. Let's take it down a notch."

She recently took her 125 crewmembers on a holiday to luxury Australian resort Hamilton Island.