梓 (zǐ) is a bound morpheme found in literary and formal compounds. It originally refers to the catalpa tree, whose wood was used for printing blocks and fine furniture. By extension, it appears in 梓里/乡梓 meaning 'one's native place' (a classical reference to planting trees around a home), and in 付梓 meaning 'to publish' (literally 'hand over to the woodblocks'). Modern usage is limited to these set expressions, so you won't see 梓 used as a stand-alone word.