What does the cryptic crossword clue "In part onshore, a charity having influence (5)" mean?

The definition is "influence". The wordplay uses a hidden word. Hidden in "in part onshoRE, A CHarity having influence" The answer is REACH.

In part onshore, a charity having influence (5)

Guardian Cryptic #29321 | 9 Across | 2024-03-04 flower