Usage of the character 再

again; once more; re-
second; another
then (after sth, and not until then)
no matter how ... (followed by an adjective or verb, and then (usually) 也 (yě) or 都 (dōu) for emphasis)

zàibài

再拜

[再拜]

to bow again
to bow twice (gesture of respect in former times)
(in letters, an expression of respect)

zàihǎo

再好

[再好]

even better

yīzài

一再

[一再]

repeatedly

zàisān

再三

[再三]

over and over again
again and again

zàiqǐ

再起

[再起]

to arise again
to make a comeback
resurgence

zàiyě

再也

[再也]

(not) any more

zàicì

再次

[再次]

once more; once again

zàiyù

再育

[再育]

to increase
to multiply
to proliferate

zàigǎi

再改

[再改]

to renew
to reform

zàidù

再度

[再度]

once more; once again; one more time

zàifàn

再犯

[再犯]

to re-offend
repeat offender; recidivist

zàixiàn

再现

[再現]

to recreate
to reconstruct (a historical relic)

zàishì

再世

[再世]

to be reincarnated

zàijiào

再醮

[再醮]

to remarry

zàilín

再临

[再臨]

to come again

zàibù

再不

[再不]

if not; if (one) does not
or else; alternatively

bùzài

不再

[不再]

no more; no longer

zàizhě

再者

[再者]

moreover
besides

zàirù

再入

[再入]

to re-enter

zàisì

再四

[再四]

repeatedly
over and over again

zàijiàn

再见

[再見]

goodbye
see you again later

zàizhì

再制

[再製]

to make more of the same thing
to reproduce
to reprocess
to remanufacture

zàishēng

再生

[再生]

to be reborn
to regenerate
to be a second so-and-so (famous dead person)
recycling
regeneration

zàishěn

再审

[再審]

to hear a case again
review
retrial

zàisài

再赛

[再賽]

to compete again (i.e. either have a rematch or, when the scores are tied, have extra time)

zàibǎn

再版

[再版]

second edition
reprint

zàishuō

再说

[再說]

to say again
to put off a discussion until later
moreover
what's more
besides

zàidú

再读

[再讀]

to read again
to review (a lesson etc)

zàizào

再造

[再造]

to give a new lease of life
to reconstruct
to reform
to rework
to recycle
to reproduce (copies, or offspring)
restoration
restructuring

zàizé

再则

[再則]

moreover
besides

zàiqiān

再迁

[再遷]

to promote again
reappointed

zàihūn

再婚

[再婚]

to remarry

zàijià

再嫁

[再嫁]

to remarry (of woman)

zàifā

再发

[再發]

to reissue
(of a disease) to recur
(of a patient) to suffer a relapse

zàijiàn

再建

[再建]

to reconstruct
to build another

zàihuì

再会

[再會]

to meet again
until we meet again
goodbye

zàishēngchǎn

再生产

[再生產]

to reproduce
reproduction

zàifāxiàn

再发见

[再發見]

rediscovery

zàizhìyán

再制盐

[再製鹽]

refined salt

zàifāshēng

再发生

[再發生]

to reoccur

zàichūxiàn

再出现

[再出現]

to reappear

zàibǎozhèng

再保证

[再保證]

to reassure

kězàishēng

可再生

[可再生]

renewable (resource)

Chén Zàidào

陈再道

[陳再道]

Chen Zaidao (1909-1993), general in the People's Liberation Army

zàilìyòng

再利用

[再利用]

to reuse

zàipínghéng

再平衡

[再平衡]

to rebalance

zàiróngzī

再融资

[再融資]

refinancing
restructuring (a loan)

zàichǔlǐ

再处理

[再處理]

reprocessing

zàibǎoxiǎn

再保险

[再保險]

reinsurance (contractual device spreading risk between insurers)

zàiyīcì

再一次

[再一次]

again

zàizhìzhǐ

再制纸

[再製紙]

recycled paper

zàizàoyè

再造业

[再造業]

recycling industry

zàishǐyòng

再使用

[再使用]

to reuse

zàizěnme

再怎么

[再怎麼]

no matter how ...

zàishēngshuǐ

再生水

[再生水]

reclaimed water; recycled water

zàijiēzàilì

再接再砺

[再接再礪]

variant of 再接再厲／再接再厉 (zàijiēzàilì)

yīcuòzàicuò

一错再错

[一錯再錯]

to repeat errors
to continue blundering
to make continuous mistakes

zàisānzàisì

再三再四

[再三再四]

repeatedly
over and over again

yīfànzàifàn

一犯再犯

[一犯再犯]

to keep doing (the wrong thing)

shíbùzàilái

时不再来

[時不再來]

Time that has passed will never come back. (idiom)

zàihǎobùguò

再好不过

[再好不過]

couldn't be better
ideal
wonderful

zàishēngzīyuán

再生资源

[再生資源]

renewable resource

qīngchūnbùzài

青春不再

[青春不再]

lit. one's youth will never return
to make the most of one's opportunities (idiom)

zàijiēzàilì

再接再厉

[再接再厲]

to continue the struggle (idiom); to persist
unremitting efforts

zàishēngfùmǔ

再生父母

[再生父母]

like a second parent (idiom); one's great benefactor

ēntóngzàizào

恩同再造

[恩同再造]

your favor amounts to being given a new lease on life (idiom)

dōngshānzàiqǐ

东山再起

[東山再起]

lit. to return to office after living as a hermit on Mount Dongshan (idiom); fig. to make a comeback

zàishēngyīxué

再生医学

[再生醫學]

regenerative medicine

zàishēngnéngyuán

再生能源

[再生能源]

renewable energy source

zàishuāisānjié

再衰三竭

[再衰三竭]

weakening and close to exhaustion (idiom); in terminal decline
on one's last legs

zàishēngzhìdòng

再生制动

[再生制動]

regenerative braking

zàizàoshǒushù

再造手术

[再造手術]

reconstructive surgery

zàishēngránliào

再生燃料

[再生燃料]

renewable fuel

zàihuóhuàjiǎshuō

再活化假说

[再活化假說]

reactivation hypothesis

cáiwùzàibǎoxiǎn

财务再保险

[財務再保險]

financial reinsurance (aka "fin re")

kězàishēngzīyuán

可再生资源

[可再生資源]

renewable resource

kuòdàzàishēngchǎn

扩大再生产

[擴大再生產]

to expand production
to reproduce on an extended scale

zàijiànquánlěidǎ

再见全垒打

[再見全壘打]

walk-off home run

bùkězàishēngzīyuán

不可再生资源

[不可再生資源]

nonrenewable resource

kěyī'érbùkězài

可一而不可再

[可一而不可再]

may be done once and once only; just this once

wénzizàixiǎoyěshìròu

蚊子再小也是肉

[蚊子再小也是肉]

lit. even a mosquito, though tiny, provides some nourishment (idiom)
fig. it's better than nothing

zàishēngbùliángxìngpínxuè

再生不良性贫血

[再生不良性貧血]

aplastic anemia

yī'érzài,zài'érsān

一而再，再而三

[一而再，再而三]

again and again

yǒujièyǒuhuán,zàijièbùnán

有借有还，再借不难

[有借有還，再借不難]

return what you borrowed on time, you may borrow again next time (idiom)

jībùkěshī,shībùzàilái

机不可失，失不再来

[機不可失，失不再來]

opportunity knocks but once (idiom)

hǎojièhǎohuán,zàijièbùnán

好借好还，再借不难

[好借好還，再借不難]

see 有借有還，再借不難／有借有还，再借不难 (yǒujièyǒuhuán,zàijièbùnán)

jībùkěshī,shíbùzàilái

机不可失，时不再来

[機不可失，時不再來]

Opportunity knocks but once. (idiom)

huāyǒuchóngkāirì,rénwúzàishàonián

花有重开日，人无再少年

[花有重開日，人無再少年]

a flower may blossom again, but a person cannot get young again (proverb)