Like some loving cooing phrase used as an extension of chicka or chick to make it sound more like that's not a chick that's a happy chickadee..
Or a woman who is hot as hell and knows what she is look-in for..
Or that one is looking to nest up...
Or a chick who is ready to rock and roll on a dime to whoop some as like a bird protecting a nest..
"That's one rock-in chickadee"