nibble (away) at something
phrasal verb with nibble verb uk/ˈnɪb.əl/ us/ˈnɪb.əl/
逐渐消耗，蚕食
to slowly reduce something
Even when inflation is low, it nibbles away at people's savings, reducing their value considerably over several years. 即便通货膨胀率不高，它也在慢慢消耗人们的储蓄，在几年间使其大大贬值。