The most common and most likely answer to this crossword clue is the 6 letter word OBLATE
I've seen this crossword clue in The Daily Telegraph
O
B
L
A
T
E
More clues leading to the result OBLATE
- One dedicated old boy no longer with us
- Religious person giving description of our earthy sphere
- Religious person died recently
- Religious devotee died but not in time
- Religious devotee, twice deceased
- Shaped like the earth, but able to change
- One brought in to convene maybe departed twice?
- Dedicated bishop inside recently after ignoring fine
- Religious type delayed by old bishop
- Old bishop recently seen as dedicated person
Buddy explains!

The straight part
We know that "Offered up/a spheroid" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case offered up/a spheroid = oblate.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 OBLATE mean?
OBLATE noun- A person dedicated to a life of religion or monasticism, especially a member of an order without religious vows or a lay member of a religious community.
- A child given up by its parents into the keeping or dedication of a religious order or house.
- Flattened or depressed at the poles.
- To offer as either a gift or an oblation.