[bash] How to retrieve the first word of the output of a command in bash?

Using shell parameter expansion %% *

Here is another solution using shell parameter expansion. It takes care of multiple spaces after the first word. Handling spaces in front of the first word requires one additional expansion.

string='word1    word2'
echo ${string%% *}
word1

string='word1    word2      '
echo ${string%% *}
word1

Explanation

The %% signifies deleting the longest possible match of * (a space followed by any number of whatever other characters) in the trailing part of string.