蠶食鯨吞

1. • to nibble like a silkworm or swallow like a whale (idiom)

     lit.

2. • to seize (territory etc) incrementally or wholesale

     fig.

Character by character

• 蠶(cán)silkworm
• 食(shí)eat
• 鯨(jīng)whale
• 吞(tūn)swallow