Alcazar
The Spanish name Alcazar is really a Spanish transcription for Arabic al-qaṣr meaning “the castle”. Like Spanish Castro, this stems from Latin castra / castrum. The ultimate origin lies perhaps with Semitic qṣr for “cut-off”, which also seems related to Caesar. But wherever that word came from, we know what it means for the spooks: These names mark them as natural “palace”-born parasites, “cut off” from regular lowborn folks.
Spanish, Latin, Arabic alcazar, al-qaṣr, castra = castle, palace
Alcazar : a surname; From Spanish Alcázar, from alcázar, from Arabic اَلْقَصْر (al-qaṣr, “the castle”), itself from Latin castrum (“castle”). Cognate with castle. — English (Wikt)
Castro : a surname; Probably ultimately from Latin castra (“military camp”). — Spanish (Wikt)
castrum : castle, fort, fortress; (chiefly plural) camp, especially a military camp — Latin (Wikt)
قَصْر qṣr qaṣr : large stone building, castle, palace, fortress; From Aramaic קַצְרָא (qaṣrā), from Latin castrum. Cognate to Classical Syriac ܩܰܨܪܳܐ (qaṣrā), Hebrew קְצָרָה (qəṣārâ), Byzantine Greek κάστρον (kástron). — Arabic (Wikt)