The most common and most likely answer to this crossword clue is the 7 letter word SMITTEN
I've seen this crossword clue in The Daily Telegraph
S
M
I
T
T
E
N
More clues leading to the result SMITTEN
- Clear — chap’s back in love
- Singular protection for pugilist in love
- It's clear your setter's head over heels in love!
- Son has glove taken
- Small winter garment swept off one's feet
- Struck with top of southpaw’s boxing glove
- Little boy’s about 10 and in love
- Onset of smallpox in Germany, with x number affected
- At first she’s clear I’m back in love
- In love and almost ecstatic holding hand
Buddy explains!

The straight part
We know that "in love" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in love = smitten.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 SMITTEN mean?
SMITTEN verb- To hit, to strike.
- To strike down or kill with godly force.
- To injure with divine power.
- To put to rout in battle; to overthrow by war.
- To afflict; to chasten; to punish.
- (now only in passive) To strike with love or infatuation.
- Affected by an act of smiting.