"Why". Science is the study of everything and trying to figure out how and why things work.
One scientific word that begins with "B" is "biology," which is the study of living organisms.
Wonderful.
Wholeheartedly is a long word. It begins with the letter w.
One such word is witty.
logic
dewdeclawdisallowdisavowdrawdrew
· weather satellites
well-known
· windy
Weightlessness is a space word. It begins with the letter w.
The Holocaust was wicked. It begins with W.
No Spanish words begin with W but some words borrowed from English, like 'walkman', 'water' (meaning 'toilet'), 'waterpolo' and 'whisky'.