Lynn Loud, Sr. (or Dad) is the father of Lincoln and his sisters. Lynn Sr. is a supporting character in the first season, and a major character from Season 2-present.
Lynn Sr. is stern, and often calls a halt to his kids' fights, but he loves and cares about them. He also loves his wife, and often acts playfully romantic towards her. He has been shown to have a childlike side at times, even sometimes taking part in his kids' antics, when it's all in good fun. He's also the more sensitive of the two parents, often necessitating his wife, and stepping in whenever he needs to pull himself together.
On a side note, he seems to enjoy jokes and dancing. He is shown to dance on occasions in episodes such as "The Loudest Yard", "Ties That Bind", "Come Sale Away", "House Music", and "Lock 'N' Loud". In addition, it is mentioned in "A Tattler's Tale" that he won a dancing contest, and had a disco ball trophy that Lincoln broke. In addition, in "Sleuth or Consequences" he mentions enjoying karaoke. On occasion, he enjoys Luan's jokes, and tries making his own, which appeal to Luan as well, as shown in "Raw Deal".
He's also shown to be quite a coward, as he screams and faints at the sight, sound, and idea of spiders, Lana's mud wrestling, horror movies, and Halloween.
Appearance
Lynn Sr. wears a sea green sweater over a light-green checkered collar and cuffs, and brown slacks. He has a long pointy nose, brown eyebrows, and curly brown hair that is thinning on the top.
In "House Music", when he is playing the cowbell, he wears a yellow-striped shirt, and green pants which his underwear was seen. In his youth, he sported a mustache. His hair was also straighter and parted in the middle.
Lynn Sr.'s entire face was never shown during the first season. His face was revealed along with Rita's face in the Season 2 premiere, "11 Louds a Leapin'".
This seems to be parodied at the beginning of "Suite and Sour", as the first few seconds of the episode keep their faces hidden, as if their reveal never happened, only to show them afterwards.
Similar to Mr. and Mrs. Turner from The Fairy Odd Parents where their faces aren't shown in the shorts and was officially shown in Season 1.
Out of his children, he's the closest to Luna, Luan, Lynn, and Lana.
He is the first character in the series, apart from Lincoln, to speak to the audience. This instance occurred at the end of "It's a Loud, Loud, Loud, Loud, House".
His personality is very similar to that of Tom Harper from Nicky, Ricky, Dicky & Dawn, as well as Harold Buttowski from Kick Buttowski: Suburban Daredevil, who are also father characters played by Brian Stepanek.
It is revealed in "House Music", that he used to be in a band, but got kicked out due to playing his cowbell too much, even when they were not practicing.
Lynn - Love for sports ("Toads and Tiaras" and "Attention Deficit").
In "Fed Up", it is revealed that Lynn Sr.'s astrological sign is Libra, which means he was born on or somewhere between September 23 and October 22.
The colors and styles of clothing that the Loud and McBride parents wear correspond with each other. Lynn Sr. and Harold both wear sweaters, and brown loafer shoes. They also both have thinning hair.
