Strong's #1003: biyraniyth (pronounced bee-raw-neeth')
from 1002; a fortress:--castle.
Brown-Driver-Briggs Hebrew Lexicon:
ּ
bı̂yrânı̂yth
1) fortress, fortified place
Part of Speech: noun feminine
Relation: from H1002
Usage:
This word is used 2 times:
2 Chronicles 17:12: "great exceedingly; and he built in Judah castles, and cities of store."
2 Chronicles 27:4: "of Judah, and in the forests he built castles and towers."