虽
suī · HSK 6
though
🐛 口 mouth + 虫 bug: even if a bug flies in, you carry on
The character stacks mouth over insect. A bug landing in your mouth is awful, but you push through anyway — capturing the concessive sense of although or even if.
虽 — mouth 口 + insect 虫, with 唯-like phonetic
虽 is the simplified form of 雖. The traditional character combined 唯 (phonetic, giving the 'sui' sound) with 虫 (insect), originally referring to a kind of lizard. Over time the meaning shifted entirely to the grammatical sense 'although', and the original creature reading was lost.