Yash Gupta, Disha Delphy Public School, Jaipur (KOTA).

Falciform - sound like a s right there but there's a 'c' instead.
Onomatopoeia- ending vowels make it confusing.
Diphtheria- has dual pronunciation which lead to different spellings
Bloemfontein- capital of south Africa. Take care of the geography part.
Sashimi- quite easy if you know origins, otherwise tough to spell
Arachnid- often mistaken for a k where there's a CH
Committee- don't miss a single doublet!!
Boutonniere- very complex pronunciation
Cirrhosis- disease.