Verb (5-dan, む, transitive)
1. to insert; to put in; to thrust in; to plug in
そっとズボンのポケットに、丸いケースが差し込まれた。A round case was gently inserted into the pocket of the trousers.
Verb (5-dan, む, intransitive)
2. to come in (of light); to shine in; to stream in; to pour in
also written as 射し込む
どこかから光が差し込んでいるようだ。It seems that light is streaming in from somewhere.
3. to have a griping pain (in the stomach, chest, etc.)