Wordnet 3.0
NOUN (1)
1.
the title of the Holy Roman Emperors or the emperors of Austria or of Germany until 1918;
The Collaborative International Dictionary of English v.0.48:
Kaiser \Kai"ser\, n. [Gr., fr. L. Caesar. Cf. Kesar, and
Czar.]
The ancient title of emperors of Germany assumed by King
William of Prussia when crowned sovereign of the new German
empire in 1871.
[1913 Webster]
WordNet (r) 3.0 (2006):
Kaiser
n 1: the title of the Holy Roman Emperors or the emperors of
Austria or of Germany until 1918
Moby Thesaurus II by Grady Ward, 1.0:
24 Moby Thesaurus words for "Kaiser":
Dalai Lama, Holy Roman Emperor, Inca, ardri, bey, cacique, caesar,
cham, czar, kaid, khan, mikado, negus, padishah, pendragon,
pharaoh, rig, sachem, sagamore, shah, sheikh, shogun, tenno,
tycoon