Assuming that the cursor is at the first character of the word simply do this in command mode:
y is for yank and w is for word.
Other ways of doing the same thing which are not as efficient:
the v starts visual select mode. e tells vim to move to end of word. y yanks or copies the word. to delete replace y with x.
if the cursor is somewhere in the middle of the word, add a b before the command as in: