twenty; 20

2nd day of the month

World War II

carbon dioxide CO2

the Second (of numbered kings); second generation (e.g. Chinese Americans)

second (i.e. number two); second time; twice; (math.) quadratic (of degree two)

second brother

February; second month (of the lunar year)

grade 2; second class; category B

indirectly acquired; second-hand (information, equipment etc); assistant

second generation

both; both of them; neither

second class; second-rate

double; repeated twice

20th century

second-rate; second-tier

see 二郎神[Er4 lang2 shen2]

duet

second-hand car

2D barcode; matrix code; (esp.) QR code

deputy leader; the second-in-command

again; twice; (music) second (i.e. an interval between adjacent notes)

(slang) fool; dunce; foolishly cute person

biceps muscle

see 二七區|二七区[Er4 qi1 Qu1]

negotiable price; (chemistry) divalent; bivalent

中伏[zhong1 fu2]

two sides

urination and defecation

duality; dual; bipolar; binary

16; sixteen

second part; the equinox

second officer (of ship); second mate

(coll.) silly but cute husky (dog)

second tone

mistress; second wife; lover

(coll.) (usu. of women in former times) to marry for a second time; second marriage; person who remarries

second child; second baby

(law) second instance; second trial

(slang) idiot; idiotic

disloyalty; half-heartedness; duplicity

second branch of an extended family; concubine

index finger

second of the five night watch periods 21:00-23:00 (old)

secondly, ...

second bouillon, a light broth obtained by reboiling ingredients that were previously used to make a full-strength first bouillon 頭湯|头汤[tou2 tang1]

2nd rank of candidates who passed the imperial examination (i.e. 4th place and up)

Second Chinese Character Simplification Scheme (abbr. for 第二次漢字簡化方案|第二次汉字简化方案[Di4 er4 Ci4 Han4 zi4 Jian3 hua4 Fang1 an4])

variant of 二黃|二黄[er4 huang2]