English

Noun

A1

1. A standard paper size, defined by ISO 216 to have dimensions: 841 x 594 mm (840.90 x 594.60 mm)

   a sheet of A1 paper

See also

• (A paper sizes): 2A0   A0   A1   A2   A3   A4   A5   A6   A7   A8   A9   A10

Etymology 2

From various rating systems, as that of Lloyd's of London or the condition of insured ships. First attested in 1837.

Alternative forms

• A-1, A 1

Adjective

A1 ‎(not comparable)

1. (informal) In good health.
2. (informal) In excellent or top condition.
3. (of a ship) First-class. (Compare A 2 and A 3, which are inferior grades.)

Etymology 3

Proper noun

A1

1. Under the International Union of Railways ("UIC") classification system, a steam locomotive that has two coupled driving wheels followed by two trailing wheels, with no leading wheels; also called an 0-2-2.

English

Adjective

a1 ‎(not comparable)

1. first rate or excellent
2. (of a ship) in first class condition

Mandarin

Romanization

a1 (Zhuyin ㄚ)

1. Alternative spelling of ā