The most common and most likely answer to this crossword clue is the 7 letter word TROCHEE
T
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More clues leading to the result TROCHEE
- Foot of giant bird encountered in the east
- European at back of sportsmen's line after twisting right foot
- Box, perhaps containing old chief’s foot
- Say yew outside old church is poetic feature
- A foot preserved in vitro – cheek!
- Foot mythical bird put in the shoe, finally
- Foot of old companion jammed in box?
- You, once holding stone, cut foot
- Precious weight system finally replaced by revolutionary European metric unit
- Foot of fabulous bird you once squeezed
Buddy explains!

The straight part
We know that "metric unit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case metric unit = trochee.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 TROCHEE mean?
TROCHEE noun- A metrical foot in verse consisting of a stressed syllable followed by an unstressed syllable.