IS

complete consistent metric system of units for scientists (with basic quantities of length, time, electric current, temperature, luminous intensity, amount of substance and mass)

v. exist; occur, happen; occupy a position or place

Is is the third-person singular verb form of the copula in the English language.
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.is is the Internet country code top-level domain (ccTLD) for Iceland. Foreign entities have to appoint a local representative in Iceland and may only register domain names that correspond to their word trademarks. “.is” is derived from the first two letters of the country’s name in Icelandic, Ísland (accents are invalid in URLs).
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In meta-ethics, the is-ought problem was raised by David Hume (Scottish philosopher and historian, 1711–1776), who noted that many writers make claims about what ought to be on the basis of statements about what is. But there seems to be a big difference between descriptive statements (about what is) and prescriptive statements (about what ought to be).
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Verb
1. have the quality of being; (copula, used with an adjective or a predicate noun); "John is rich"; "This is not a good answer"
(hyponym) look
2. be identical to; be someone or something; "The president of the company is John Smith"; "This is my house"
3. occupy a certain position or area; be somewhere; "Where is my umbrella?" "The toolshed is in the back"; "What is behind this behavior?"
(hyponym) stretch, stretch along
4. have an existence, be extant; "Is there a God?"
(synonym) exist
(hyponym) come
(derivation) being, beingness, existence
5. happen, occur, take place; "I lost my wallet; this was during the visit to my parents' house"; "There were two hundred people at his funeral"; "There was a lot of noise in the kitchen"
6. be identical or equivalent to; "One dollar equals 1,000 rubles these days!"
(synonym) equal
(hyponym) equate, correspond
7. form or compose; "This money is my only income"; "The stone wall was the backdrop for the performance"; "These constitute my entire belonging"; "The children made up the chorus"; "This sum represents my entire income for a year"; "These few men comprise his entire army"
(synonym) constitute, represent, make up, comprise
(hyponym) make
8. work in a specific place, with a specific subject, or in a specific function; "He is a herpetologist"; "She is our resident philosopher"
(synonym) follow
(hyponym) vet
9. represent, as of a character on stage; "Derek Jacobi was Hamlet"
(synonym) embody, personify
(hypernym) typify, symbolize, symbolise, stand for, represent
(hyponym) body, personify
10. spend or use time; "I may be an hour"
(hypernym) take, occupy, use up
11. have life, be alive; "Our great leader is no more"; "My grandfather lived until the end of war"
(synonym) live
(verb-group) survive, last, live, live on, go, endure, hold up, hold out
(derivation) organism, being
12. to remain unmolested, undisturbed, or uninterrupted -- used only in infinitive form; "let her be"
(hypernym) stay, remain, rest
13. be priced at; "These shoes cost $100"
(synonym) cost
(hyponym) set back, knock back, put back

intelligence service, organization which is responsible for collecting and studying information relevant to national security

v. be