Priest, whose Central career began in the 2003/04 season, scored a brisk 103 off 133 balls, including 11 boundaries, before giving Amy Rendel a catch off a Kelly Anderson delivery.
Central were two for 57 when Sara McGlashan joined Priest at the crease and the two New Zealand internationals put on 71 runs for the third wicket before McGlashan departed for 42, bowled by Anderson.
Canterbury's reply was built around a patient 78 by Mandie Goodiman, 69 not out off 66 balls by Maria Fahey and 39 off 35 balls by Amy Satterthwaite which saw them reach 251 for three in 47.6 overs.
It was Canterbury's first win in three rounds and the loss saw Central drop from second to fifth.
At Upper Hutt, competition leaders Wellington lost by eight runs to Auckland who moved into second place after scoring their second win in three rounds. They have eight points, one behind Wellington.
Auckland, batting first put 165 on the board with Katie Perkins leading the way with a 42.
They successfully defended their total with bowlers Rosie Cox, 3-26, and Holly Huddleston, 3-39, each collecting a brace. Megan Tremaine chimed in with 2-25 which included the vital wickets of Wellington top order bats, Sarah Bradbury for six and Amanda Cooper for two.
Wellington's Megan Wakefield top scored for her side with 50, her tenth half century at this level.
At Whangarei, Otago notched 222 for nine with Sarah Tsukigawa scoring 73 and Katey Martin a 51 but Northern Districts did not get the chance to reply after rain forced the match to be abandoned.
