first

at first blush: seeblush.

at first hand directly or from personal experience.

cast the first stone: seestone.

first among equals: seeequal.

first blood: seeblood.

first come, first served used to indicate that people will be dealt with strictly in the order in which they arrive or apply.

first off as a first point; first of all. informal

2010Jon McGregorEven the Dogs There's a patch in the underpass we'll try first off, … should get enough for the first bag of the day.

first past the post

1 (of a contestant, especially a horse, in a race) winning a race by being the first to reach the finishing line.

2 denoting an electoral system whereby a candidate or party is selected by achievement of a simple majority.

first thing early in the morning; before anything else.

first things first important matters should be attended to before anything else.

☞ First Things First was the title of a book by George Jackson, subtitled 'Addresses to young men' (1894).

first up

1 first of all.

2 at the first attempt.

Australian

get to first base: seebase.

in the first flush: seeflush.

of the first order (or magnitude) used to denote something that is excellent or considerable of its kind.

☞ In astronomy, magnitude is a measure of the degree of brightness of a star. Stars of the first magnitude are the most brilliant.

of the first water extreme or unsurpassed of its kind.

☞ If a diamond or other gem is of the first water it possesses the greatest possible degree of brilliance and transparency. In this metaphorical use, however, the phrase often refers to someone or something regarded as undesirable, e.g. a bore of the first water.