Humans live in a four dimensional world: three spatial dimensions and the dimension of time. For most of human history, humans have used nature for telling time. Time periods were marked by the sun, the moon, and the seasons. With the demands of religion and industrialization, however, humans superimposed mechanical time on their daily lives. With this mechanical time, telling time became different and some new words and concepts entered into English.
Time:
The English word “time” has its origins in the Proto-Indo-European *di- which means “cut up, divide.” In prehistoric German this became *ti- and with the addition of the suffix *-mon- it became “timon” which evolved into the English “time.”
Clock:
The clock, a mechanical device for measuring time, was first developed for European Christian monasteries. Social psychologist Robert Levine writes in his book A Geography of Time:
“The first clocks were invented for one very specific purpose: to inform pious monks when it was time to pray.”
Levine goes on to report:
“The first clocks were developed to simply sound bells at the appointed prayer hours.”
This action of striking a bell provides us with an important clue as to the etymology of the English word “clock.” The origins of the Middle English “clok” can be traced to the Middle Dutch “clocke” which came from the Medieval Latin “clocca” meaning “bell.” “Clocca” did not enter Latin until the seventh-century and appears to have its origins in the Old Irish “clocc.” Unlike continental European Christianity, Irish Christianity was monastic and thus bells were a common feature of monastic life. The Old Irish “clocc” moved to the continent and into Latin as the Irish monastic movement came to the continent.
In English, “clock” replaced the Old English “dægmæl” which was based on “dæg” (“day”) and “mæl” (“measure, mark”).
Telling time today usually involves the time “of the clock,” which is contracted to “o’clock.”
Hour:
The word “hour” entered into English in the mid-thirteenth century from the Old French “hore” meaning “one-twelfth of a day (measured from sunrise to sunset).” The Old French “hore” came from the Latin “hora” meaning “hour, time, season” which came from the Greek “hora” meaning “any limited time.” The Greek concept of “hora” was rather vague and could be used for any period of time, including the seasons. The Greek “hora” comes from the Proto-Indo-European “*yor-a-” which is based on the root “*yer-” meaning “year, season.”
The ancient Greek astronomers got the idea of dividing the day into twelve parts from the Babylonians. While they divided the day into twelve parts, they continued to divide the night into four watches. Since the amount of daylight varies according to the season, the length of the hour was not constant. It wasn’t until sometime in the fourth century that Europeans began to use the idea of the hour having a fixed length. For the next eight centuries, however, many Europeans would continue to make distinctions between temporary (unequal) hours and sidereal (equal) ones.
The “h” in “hour” is not pronounced and thus in the spoken language there is no distinction between “hour” and “our.” In Old English “stund” meant “hour, period of time, point of time” and “tid” meant “time.” The Old English “tid” became “tide” in modern English. The use of “tide” referring to time can still be seen in words such as “yuletide.”
Minute and Second:
The English “minute,” meaning “one-sixtieth of an hour,” was adopted in the late fourteenth century from the Old French “minut” which comes from the Latin “minuta.” The concept of the minute as a unit of time begins with the mathematician Ptolemy who used “pars minuta prima” meaning “first small part” for one-sixtieth of a circle and since clock faces were round, the minute became used for one-sixtieth of an hour (one time around the clock face). The next smallest unit was “secunda minute,” which became the second.
Note: In etymologies, the * indicates that the Proto-Indo-European or prehistoric word has been reconstructed by historical linguists.