The most common and most likely answer to this crossword clue is the 6 letter word GUSHED
I've seen this crossword clue in The Guardian
G
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More clues leading to the result GUSHED
Buddy explains!
The straight part
We know that "were too effusive" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case were too effusive = gushed.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 GUSHED mean?
GUSHED verb- To flow forth suddenly, in great volume.
- To send (something) flowing forth suddenly in great volume.
- (especially of a woman) To ejaculate during orgasm.
- To make an excessive display of enthusiasm, praise, or sentiment.