great (or small) circle

A circular section of a sphere whose centre is (or is not) the centre of the sphere

reasoning in a circle

Assuming what is to be proved as the basis of the argument

run round in circles

To act in too frenzied a way to achieve anything useful

great /grāt/

adjective

1. Big
2. Large
3. Of a high degree of magnitude of any kind
4. (of a letter) capital (archaic)
5. Elevated in power, rank, station, etc
6. Pre-eminent in genius
7. Highly gifted
8. Much admired and respected
9. Chief
10. Sublime
11. Weighty
12. Outstanding
13. (with on) devoted to or obsessed by a certain thing
14. Much given to, or excelling in the thing in question
15. Favourite
16. Habitual
17. In high favour or intimacy
18. In a high degree
19. On a large scale
20. Excellent (informal, often ironic)
21. Larger in size than others of the same kind, species, etc (biology)
22. In combination, indicating one degree more remote in the direct line of descent (as in great-grandfather, great-grandson and similarly great-great-grandfather and so on indefinitely)
23. Pregnant, teeming (archaic)
24. Swelling with emotion (archaic)

noun

1. Someone who has achieved lasting fame
2. (with the) used collectively for those people who have achieved lasting fame
3. Bulk, mass (obsolete)
4. Whole (obsolete)
5. Wholesale (obsolete)

adverb (informal)

Very well

greatˈen transitive verb

To make great or greater

intransitive verb (obsolete)

To become great

greatˈer adjective

1. Compar of great
2. (with geographical names) in an extended sense (eg Greater London)

greatˈly adverb

greatˈness noun

Greats plural noun

1. The final honours examinations of the School of Literae Humaniores (Classical Greats) or of Modern Philosophy (Modern Greats) at Oxford University
2. The course leading to these

great ape noun

Any of the larger anthropoid apes, such as the chimpanzee, gibbon, gorilla and orang-utan

great auk noun

A large, flightless auk once common in N Atlantic areas, now extinct

greatˈ-aunt noun

A grandparent's sister or a grandparent's brother's wife

Great Bear noun

Ursa Major

greatˈ-bellied adjective (archaic; Shakespeare)

Pregnant

Great Britain noun

England, Scotland and Wales

great circle noun

A circle on the surface of a sphere whose centre is the centre of the sphere

greatˈcoat noun

An overcoat

Great Dane noun

One of a breed of very large smooth- (and short-)haired dogs

greatˈ-grandˈchild noun

The child of a grandchild

greatˈ-grandˈfather noun

The father of a grandparent

greatˈ-grandˈmother noun

The mother of a grandparent

great gross noun

A unit of quantity equal to 12 gross (1728)

greatˈ-hearted adjective

1. Having a great or noble heart
2. High-spirited
3. Magnanimous

great-heartˈedness noun

greatˈ-nephew noun

The grandson of one's own or one's spouse's brother or sister

greatˈ-niece noun

The granddaughter of one's own or one's spouse's brother or sister

great primer see primer

great schism noun (historical)

The great Eastern schism or the Western schism (see under schism)

Great Sea noun (archaic)

The Mediterranean

Great Seal noun

A seal kept by the Lord Chancellor or Lord Keeper and used on the most important state papers

great tit noun

A kind of tit (see tit¹), Parus major, with yellow, black and white markings

great toe see under toe

greatˈ-uncle noun

A grandparent's brother or a grandparent's sister's husband

Great War noun

A term applied esp to the war of 1914–18

Great White Way noun

1. A nickname for Broadway in New York
2. Any brightly lit street with theatres, etc

great year noun (astronomy)

The length of time (about 25800 years) it takes for the equinoctial points to make a complete revolution

Great Scott!

An exclamation of surprise

the Great and the Good

(an assembly of) eminent, worthy and respected public figures (often somewhat ironic in use)

the greatest (informal)

1. A wonderful, marvellous person or thing
2. The outstanding performers in their field

the great unwashed

A contemptuous term for the general populace