Latin or hospiticīda , from *hospiticīdium ( hospes “ host, guest ”) + ( -cīda “ killer ”); equivalent to + . -cide  
hospiticide ( , countable and uncountable plural ) hospiticides
( rare ) One who kills his guest or host.
1837, Edward Smallwood, Manuella, the Executioner’s Daughter ; A Story of Madrid, volume II, pages 275–276:
Armed with the weapon which was destined to destroy himself, Imnaz sprang down the ladder, — found the door, and, emerging from the abode of crime, sought a more secure resting place, leaving his hostess to discover, with return of day, in whose blood were imbrued the hands of an
( rare ) The act of a guest killing his host or vice versa, or an instance thereof.
1837, Edward Smallwood, Manuella, the Executioner’s Daughter ; A Story of Madrid, volume II, page 261:
Anniversary of the Massacre of the Prado — the Defeat of Quesada — Murderous Reprisals —
( one who kills a guest or host ) : Glossographia; or, a dictionary interpreting the hard words of whatsoever language, now used in our refined English tongue by Thomas Blount (1656)
( act of a guest killing a host or vice versa ) : A Dictionary of Words and Phrases Used in Ancient and Modern Law by Arthur English (1987; Wm. S. Hein Publishing; ISBN 0837721040), page 423
^ “Hospiʹticide” listed on page 407 of part I of volume 5 of (1928): A New English Dictionary on Historical Principles Hospiʹticide. rare — o. [ad. rare Latin hospiticīda, f. hospes, hospit- guest + -cīda, -cide i.] One who kills his guest or host. (Blount Glossogr. 1656.)
^ “ hoˈspiticide” listed in the Oxford English Dictionary (2nd edition, 1989)