The most common and most likely answer to this crossword clue is the 10 letter word REFERENCES
I've seen this crossword clue in The Guardian
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More clues leading to the result REFERENCES
Buddy explains!
The straight part
We know that "Testimonials" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case testimonials = references.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 REFERENCES mean?
REFERENCES noun- A relationship or relation (to something).
- A measurement one can compare to.
- Information about a person, provided by someone (a referee) with whom they are well acquainted.
- A person who provides this information; a referee.
- A reference work.
- That which serves as a reference work.
- The act of referring: a submitting for information or decision.
- A relation between objects in which one object designates, or acts as a means by which to connect to or link to, another object.
- (academic writing) A short written identification of a previously published work which is used as a source for a text.
- (academic writing) A previously published written work thus indicated; a source.
- An object containing information which refers to data stored elsewhere, as opposed to containing the data itself.
- (character entity) A special sequence used to represent complex characters in markup languages, such as ™ for the ™ symbol.
- Appeal.
- To provide a list of references for (a text).
- To refer to, to use as a reference.
- To mention, to cite.
- To contain the value that is a memory address of some value stored in memory.