The most common and most likely answer to this crossword clue is the 7 letter word SINCERE
I've seen this crossword clue in The Times
S
I
N
C
E
R
E
More clues leading to the result SINCERE
- Frank's following on
- Offence by Charlie before becoming genuine
- Seeing that on, this must be genuine
- Seeing that note above board
- Heartfelt selection of words in ceremony
- Straight after embracing queen
- Genuine error — Queen held in church
- Open all the time after resistance ended at front
- Because religious education is true
- Seeing that Religious Education’s genuine
Buddy explains!

The straight part
We know that "genuine" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case genuine = sincere.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SINCERE mean?
SINCERE adjective- Genuine; meaning what one says or does; heartfelt.
- Meant truly or earnestly.
- Clean; pure