无穷

endless / boundless / inexhaustible

not to have / no / none / not / to lack / un- / -less

poor / destitute / to use up / to exhaust / thoroughly / extremely / (coll.) persistently and pointlessly

endless / boundless / infinite

boundless joy

leaving a rich aftertaste / (fig.) memorable / lingering in memory

infinitesimal (in calculus) / infinitely small

it will cause no end of trouble (idiom)

infinite set (math.)

to have disastrous consequences

to have disastrous consequences / also written 貽害無窮|贻害无穷[yi2 hai4 wu2 qiong2]

extraordinary strength / super strong / strong as an ox

if you beat the snake without killing it, endless evils will ensue (idiom)

infinite sequence

point at infinity (math.) / infinitely distant point