Christina María Aguilera ( AG-il-AIR-ə, Spanish: [kɾisˈtina maˈɾi.a aɣiˈleɾa]; born December 18, 1980) is an American singer, songwriter, actress, and television personality. Recognized as an influential figure in music and having received widespread public interest, she is noted for her four-octave vocal range, use of the whistle register, and incorporating controversial themes into her music. Referred to as the "Voice of a Generation", she was also named a Disney Legend, in recognition for her contributions to The Walt Disney Company.

After appearing on The All-New Mickey Mouse Club (1993–1994) as a child, Aguilera recorded the theme song, "Reflection", for the animated film Mulan (1998) and signed a record deal with RCA Records. She rose to fame in 1999 with her self-titled debut album which gained three number one singles on the US Billboard Hot 100 including "Genie in a Bottle", "What a Girl Wants" and "Come On Over Baby (All I Want Is You)". Seeking a departure from her teen idol image, Aguilera took on a more provocative image and released Stripped (2002), which went on to become one of the best-selling albums of the 21st century. After another old-school inspired musical reinvention, she released the critically praised Back to Basics (2006). Throughout these periods, she amassed various worldwide hits including the singles "Lady Marmalade" and "Beautiful".

During the early 2010s, Aguilera released a string of collaborations which peaked at top ten on the Hot 100 including "Moves like Jagger", "Feel This Moment" and "Say Something"; the first of these topped the chart making Aguilera one of the few artists to reach the number one spot over three decades. She has since performed in two concert residencies. Outside of music, she also starred in the film Burlesque (2010) and contributed to its soundtrack, earning a Golden Globe Award nomination. Her concurrent ventures included a role in the series Nashville (2015), roles in films The Emoji Movie (2017) and Zoe (2018), becoming an ambassador for the World Food Programme (WFP), co-founding the company Playground, and serving as a coach on the reality competition show The Voice (2011–2016).

Aguilera is one of the best-selling music artists of all time, with over 100 million records sold worldwide. She has been named one of the most successful artist of the 2000s decade by Billboard and has been referred to as one of the greatest vocalists of all time. She has since been regarded as one of the most influential Latin artists in the entertainment industry, having helped shape the "Latin explosion" in the early 2000s. Her accolades include five Grammy Awards, two Latin Grammy Awards, six ALMA Awards, two MTV Video Music Awards (VMA), a Billboard Music Award, a Guinness World Record, and a star on the Hollywood Walk of Fame.