飲み込む， 呑み込む， 飲みこむ， 呑みこむ， のみ込む， 飲込む， のみこむ
1. to swallow, to gulp down
2. to understand, to grasp, to take in, to catch on, to learn
3. to engulf, to swallow up
4. to be filled with (people), to contain
5. to swallow (one's words), to suppress (a yawn, tears, etc.), to stifle, to hold back
tbd