What does the cryptic crossword clue "Sat next in order to see navigational instrument (7)" mean?

The definition is "instrument". The wordplay uses an anagram. anagram of SAT + NEXT = SEXTANT; definition: "instrument" The answer is SEXTANT.

Sat next in order to see navigational instrument (7)

Daily Mail Cryptic #17231 | 18 Down | 2023-11-17 flower