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Results found in several dictionaries: Collins, Collaborative Dictionary
combat trousers 
  npl pantalon de treillis  m  
He was wearing black combat trousers and a hooded fleece.   

Collaborative Dictionary     English-French
combat exp. de combat Reverso General Dictionary 
combat n. le combat Reverso General Dictionary 
embattled exp. 1) engagé dans des combats, 2) en difficulté Reverso General Dictionary 
combat v. 1) combattre (vi), 2) combattre (vt) Reverso General Dictionary 
marathon fight n. le combat de longue haleine Reverso General Dictionary 
street battle n. le combat de rue Reverso General Dictionary 
suspenders n. a pair of straps used by men for holding up trousers or pants  
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'combat trousers' also found in translations in French-English dictionary
combat de chiens pref. dog fight Reverso General Dictionary 
combat corps à corps pref. hand-to-hand fight Reverso General Dictionary 
combat corps-à-corps pref. hand-to-hand fight Reverso General Dictionary 
pantalon patte d'éléphant pref. bell-bottom trousers Reverso General Dictionary 
pantalon patte d'éph pref. bell-bottom trousers Reverso General Dictionary 
pantalon pattes d'éf pref. bell-bottom trousers Reverso General Dictionary 
pantalon pattes d'éph pref. bell-bottom trousers Reverso General Dictionary 
porter... la culotte vt. wear the trousers Reverso General Dictionary 
animal de combat pref. fighting animal Reverso General Dictionary 
hélicoptère de combat pref. armed helicopter Reverso General Dictionary 

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