From Wiktionary, the free dictionary

Borrowed from Latin regulatus, perfect passive participle of regulō (“to direct, rule, regulate”) (see -ate (verb-forming suffix)), from regula (“rule”), from regō (“to keep straight, direct, govern, rule”). Compare regle, rail. Displaced native Old English metegian.

• IPA^(key): /ˈɹɛɡjəleɪt/
• (Indic) IPA^(key): /ˈɾɛɡ(j)ʊleʈ/
• Hyphenation: re‧gu‧late

regulate (third-person singular simple present regulates, present participle regulating, simple past and past participle regulated)

1. To dictate policy.
2. To control or direct according to rule, principle, or law.
   • 1834–1874, George Bancroft, History of the United States, from the Discovery of the American Continent, volume (please specify |volume=I to X), Boston, Mass.: Little, Brown and Company [et al.], →OCLC:

     The herdsmen near the frontier adjudicated their own disputes, and regulated their own police.

   • 2023 May 16, Cecilia Kang, “OpenAI’s Sam Altman Urges A.I. Regulation in Senate Hearing”, in The New York Times‎^[1], →ISSN, archived from the original on 16 May 2023:

     But on Tuesday, Sam Altman […] testified before members of a Senate subcommittee and largely agreed with them on the need to regulate the increasingly powerful A.I. technology being created inside his company and others like Google and Microsoft.

   • 2025 March 26, Hannah Rabinowitz, “DOJ considers abandoning the defense of federal restrictions on gun silencers”, in CNN‎^[2]:

     The NFA has been a flashpoint for advocates, who say that silencers are not frequently used in crime and believe that the silencers and other weapons regulated under the law, including machine guns and short-barreled rifles and shotguns, are protected by the Second Amendment.

3. To adjust (a mechanism) for accurate and proper functioning.

   to regulate a watch, i.e. adjust its rate of running so that it will keep approximately standard time

   to regulate the temperature of a room, the pressure of steam, the speed of a machine, etc.

4. To put or maintain in order.

   to regulate the disordered state of a nation or its finances

   to regulate one's eating habits

• rule
• ruler
• regular
• regulation
• regulator

• “regulate”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.
• William Dwight Whitney, Benjamin E[li] Smith, editors (1911), “regulate”, in The Century Dictionary […], New York, N.Y.: The Century Co., →OCLC.

• legature

rēgulāte

1. second-person plural present active imperative of rēgulō

regulate

1. second-person singular voseo imperative of regular combined with te