1. regulus - Noun
2. Regulus - Proper noun
A petty king; a ruler of little power or consequence.
The button, globule, or mass of metal, in a more or less impure state, which forms in the bottom of the crucible in smelting and reduction of ores.
A star of the first magnitude in the constellation Leo; -- called also the Lion's Heart.
Source: Webster's dictionaryNow a life of honour includes various kinds of conduct; it may include the chest in which Regulus was confined, or the wound of Cato which was torn open by Cato's own hand, or the exile of Rutilius, or the cup of poison which removed Socrates from gaol to heaven. Seneca
Modestus said of Regulus that he was "the biggest rascal that walks upon two legs." Pliny the Younger
According to Ptolemy, Hipparchus measured the longitude of Spica and Regulus and other bright stars. Source: Internet
At the time, it was known as the Year of the Consulship of Regulus and Rufus (or, less frequently, year 816 Ab urbe condita ). Source: Internet
Regulidae kinglets * Guadalupe ruby-crowned kinglet, Regulus calendula obscurus (Guadalupe, East Pacific, 20th century) :A subspecies of the ruby-crowned kinglet that has not been recorded since 1953. Source: Internet
From the 1950s to the 1970s, US Navy cruisers were large vessels equipped with heavy offensive missiles (including the Regulus nuclear cruise missile ) for wide-ranging combat against land-based and sea-based targets. Source: Internet