Which of the following options describes the plural form of 'A large suitcase typically made of leather and hinged in two equal parts.'

Portmanteau (Singular noun): 
English Meaning - A large case for carrying clothes while traveling, especially one that opens out into two parts. 
Bangla Meaning - কাপড়চোপড় বহনের জন্য চামড়ার আয়তাকার ব্যাগবিশেষ।

Plural forms: 
- Portmanteaus, Portmanteaux. 

Example Sentence - The question of how to fill this portmanteau is very important.

Source: Cambridge Dictionary.