1. adj. Having much distance from one terminating point on an object or an area to another terminating point (usually applies to horizontal dimensions; see Usage Notes below).
It's a long way from the Earth to the Moon.
2. adj. Having great duration.
The pyramids of Egypt have been around for a long time.
3. adj. Seemingly lasting a lot of time, because it is boring or tedious or tiring.
4. adj. (UK, dialect) Not short; tall.
5. adj. (finance) Possessing or owning stocks, bonds, commodities or other financial instruments with the aim of benefiting of the expected rise in their value.
I'm long in DuPont; I have a long position in DuPont.
6. adj. (cricket) Of a fielding position, close to the boundary (or closer to the boundary than the equivalent short position).
7. adj. (tennis, of a ball or a shot) That land beyond the baseline (and therefore is out).
No! That forehand is longnb....
8. adj. Occurring or coming after an extended interval; distant in time; far away.
9. adv. Over a great distance in space.
He threw the ball long.
10. adv. For a particular duration.
How long is it until the next bus arrives?
11. adv. For a long duration.
Will this interview take long?
Paris has long been considered one of the most cultured cities in the world.
12. n. (linguistics) A long vowel.
13. n. (programming) A long integer variable, twice the size of an int, two or four times the size of a short, and half of a long long.
A long is typically 64 bits in a 32-bit environment.
14. n. (finance) An entity with a long position in an asset.
Every uptick made the longs cheer.
15. n. (music) A note formerly used in music, one half the length of a large, twice that of a breve.
16. v. (transitive, finance) To take a long position in.
17. v. (intransitive) To await, aspire, desire greatly (something to occur or to be true)
She longed for him to come back.
18. adj. (archaic) On account of, because of.
19. v. (archaic) To be appropriate to, to pertain or belong to.