• 支持しじ — support
• 支店してん — branch office
• 支配しはい — control, rule
• 支出ししゅつ — expenditure
• 支援しえん — assistance
• 支給しきゅう — provision
• 支度したく — preparation
• 支流しりゅう — tributary stream

The original shape shows a hand holding a branch. The kanji implies support by holding or propping something up, and is also the base of extended meanings like assistance or structural division.

みんなで 彼かれを 支ささえました。
We all supported him together.

この支店してんは 大阪おおさかにあります。
This branch office is located in Osaka.

“シ” appears widely in compound words like 支援 and 支配. The kun-yomi “ささえる” is used in basic verbs and direct actions.