The Only Use of

cleave

in

To Kill a Mockingbird

"One time I asked her to have a chew and she said no thanks, that—chewing gum cleaved to her palate and rendered her speechless," said Jem carefully.
p. 69.8

cleaved = stuck (held tightly)

Definitions:

(1) (cleave as in: cleave through)
to split or cut through something

Ironically, this word can mean to split in two or to hold together.

Note that you may see cleaved, cleft, clove, or cloven as the past tense of this sense of cleave.
(2) (cleave as in: cleave to)
to hold firmly to something -- such as an object, a person or idea

Ironically, this word can mean to split in two or to hold together.

Note that you may see cleaved, clove, or clave as the past tense of this sense of cleave.
(3) (meaning too rare to warrant focus)
a proper noun or other word too rare to warrant focus