It wasn’t just alarm clocks that went off on New York City cellphones Monday morning. Another noise also pealed: emergency alerts. The message, which The New York Times reports may be the first of its kind, was “an electronic wanted poster” for the since-arrested suspect of recent bombings in the area.
Alerts and alarms haven’t just haven’t advanced in technology, though: these words have also come along way in etymology.

Alert
Both alert and alarm originated as Italian military phrases. Alert is from all’ erta, literally “on the watch” or “to the lookout.” Erta, a “high point,” comes from erto, “steep,” via the Latin ērigere, “to raise.” This verb also yields, among many others, English’s erect, whose sense of “raised up” parallels erto. All’, a contraction of alla, means “to the” or “on the,” ultimately from the Latin preposition ad (“to) and ille (“that,” source of the definite articles in the Romance languages).
French took up the Italian term as à l’erte, later alerte, which meant “watchful” or “vigilant” by the 16th century. The Oxford English Dictionary (OED) attests alert in 1618, though some references in the 1590s use alert as an interjection, e.g., a Castilian soldier “crying Alerto,” suggesting how the term was used a warning cry issued when the enemy was sighted.
And technically, to be on the alert, is etymologically redundant, meaning “on-the-on-the-watch.”
Alarm
Similarly, alarm is from the Italian all’ arme, an interjection and literal call to arms: “To the arms!” Arme derives from the Latin arma, source and meaning of the English arms, or “weapons.” The English name for the body part indeed shares an ancient root with Latin’s arma: the Indo-European root, *ar-, “to fit together.”
Alarm has been ringing out much longer than alert, documented by the OED around the 1400s. The word signaled a general “warning of danger” by the 1570s, specifically a “loud, hurried peal of a bell” by the 1590s. The clock-based alarm is by 1639.
The variant alarum, which may sound familiar to readers of Shakespeare, is thanks to the trilled r’s in some Romance pronunciations of the word, while larum, in a process called aphesis, silenced the initial a. Some speakers may have also confused alarum for a larum.
Yesterday’s watchtowers are today’s cellphone towers, calls to arms now calls to law enforcement. The forms of alerts and alarms, as practices and words, have no doubt changed over the centuries, but vigilance – judicious, informed, responsible – seems as called for as ever.