The Only Use of

plaque
in
The 100, by Morgan

He wanted to read on so he'd be able to tell his mother about it, but that would be tantamount to arriving in her hospital room with her memorial plaque and asking for her input on the wording.†
p. 14.6

Definitions:

(1) (plaque as in: a plaque on the wall)
a tablet with information or a message made for placement on a wall or other object
As compared to a paper notice, a plaque is made of more permanent material. Examples include:
- a brass tablet mounted on the exterior of a building to tell when it was constructed
- a tablet mounted on a monument to tell about an historic event
- a tablet given to someone to hang on the wall to acknowledge a bestowed honor
- a small piece of engraved metal mounted on a park bench to honor memory of them
(2) (plaque as in: dental plaque)
a sticky layer of germs and gunk that builds up on teeth
(3) (plaque as in: plaque in the arteries or brain)
a biological deposit that, in excess, can impede normal functioning