公約數

common factor / common divisor

public / collectively owned / common / international (e.g. high seas, metric system, calendar) / make public / fair / just / Duke, highest of five orders of nobility 五等爵位[wu3 deng3 jue2 wei4] / honorable (gentlemen) / father-in-law / male (animal)

convention (i.e. international agreement)

to weigh in a balance or on a scale

to make an appointment / to invite / approximately / pact / treaty / to economize / to restrict / to reduce (a fraction) / concise

divisor (of a number) / approximate number

to count / to count as / to regard as / to enumerate (sb's shortcomings)

number / figure / several / CL:個|个[ge4]

frequently / repeatedly

highest common factor HCF / greatest common divisor GCD