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Results found in several dictionaries: Collins, Collaborative Dictionary
mi-lourd 
  adj m light heavyweight
  nm light heavyweight

Collaborative Dictionary     French-English
lourd tribut pref. heavy toll Reverso General Dictionary 
poids lourd n. 1) heavy truck (m), 2) heavyweight (m), 3) heavy trucks (pl.m.), 4) heavyweights (pl.m.) Reverso General Dictionary 
poids lourd-léger pref. light heavyweight Reverso General Dictionary 
pétrole extra lourd n. extra heavy oil ~ 
avoir... la main lourde vt. be heavy-handed Reverso General Dictionary 
réacteur à eau lourde n. heavy water reactor ~ 
teneur en métaux lourds nm. heavy metal content Reverso General Dictionary 
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'mi-lourd' also found in translations in English-French dictionary
heavy-duty vehicle n. le poids lourd Reverso General Dictionary 
tough loss n. lourde perte  
heavyweight n. le poids lourd Reverso General Dictionary 
heavyweight exp. poids lourd Reverso General Dictionary 
heavy-duty lorries n. les poids lourds Reverso General Dictionary 
heavy-duty lorry n. le poids lourd Reverso General Dictionary 
heavy-duty truck n. le poids lourd Reverso General Dictionary 
heavy duty lorries n. les poids lourds Reverso General Dictionary 
heavy duty lorry n. le poids lourd Reverso General Dictionary 
heavy duty truck n. le poids lourd Reverso General Dictionary 
heavy duty vehicle n. le poids lourd Reverso General Dictionary 
heavy metal content n. la teneur en métaux lourds Reverso General Dictionary 
look of deep significance n. le regard lourd de sens Reverso General Dictionary 

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