Definitions:
measuring a great distance from end to end

lasting or taking a great amount of time

relatively great in extent

(of a vowel) categorized as long with regard to quality and length (e.g. in standard british english the vowel /uː/ in food is long as distinct from the short vowel /ʊ/ in good).

(of odds or a chance) reflecting or representing a low level of probability

(of shares, bonds, or other assets) bought in advance, with the expectation of a rise in price.

(of a drink) large and refreshing, and in which alcohol, if present, is not concentrated.

well supplied with

a long period

a long sound such as a long signal in morse code or a long vowel or syllable

long-dated securities, especially gilts.

for a long time

(with reference to the ball in sport) at, to, or over a great distance

have a strong wish or desire