The most common and most likely answer to this crossword clue is the 8 letter word LONESOME
I've seen this crossword clue in The Times
L
O
N
E
S
O
M
E
More clues leading to the result LONESOME
- One's honour in life less if solitary
- Wanting company to advance money, as you might say?
- Maybe needing company to advance money, as you’d say
- See setter embracing individuals lacking love
- Left with drink, therefore this writer’s feeling isolated
- Student meets someone adrift without friends in LA?
- Lacking a chum to advance money, you’d say?
- The writer supports orchestra accommodating individual solo
- Apparently out of date filling to spoil one’s omelette
- Loose men terribly in need of company?
Buddy explains!

The straight part
We know that "solitary" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case solitary = lonesome.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 LONESOME mean?
LONESOME noun- Oneself alone.
- Unhappy due to being alone; lonely.