Answer:

title

Answer	Crossword Clue
TITLE	Mister President or Madam Speaker
TITLE	Part of a promotion negotiation
TITLE	Something typically found on a spine

TITLE	Queen or knight
TITLE	Championship
TITLE	It's held by a winner
TITLE	Auto owner's proof
TITLE	Mr. or Mrs.
TITLE	Duke or dame
TITLE	Dr. or Mr.
TITLE	Boxer's reward

TITLE	Duke or duchess
TITLE	What may come with a trophy
TITLE	Proof of purchase
TITLE	Give a name to
TITLE	It might appear on a spine
TITLE	King or queen
TITLE	Sir or madam
TITLE	Info in a library search request

TITLE	Bibliographical datum
TITLE	See 13-Across
TITLE	Get a handle on?
TITLE	Dom or earl
TITLE	A challenger might go after one
TITLE	Challenger's quest
TITLE	See 30-Across
TITLE	Car owner's document

TITLE	Earl or viscount
TITLE	Line on a spine
TITLE	Deed
TITLE	Name
TITLE	Identification
TITLE	Card catalogue entry
TITLE	Card catalogue listing
TITLE	Honorific

TITLE	King's conferral
TITLE	It may change with a promotion
TITLE	It's often italicized
TITLE	Ground for a claim
TITLE	Threepeater's threepeat