Closely observant or alert; vigilant: kept a watchful eye on the clock. See Synonyms at aware, careful.(adjective)
Archaic Not sleeping; awake.(adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "watchful" in a sentence
"MESSNER: No. He's doing what they call watchful waiting and he's doing fine."
""Rather than give everybody an antibiotic hoping to find the ones with bacteria, our findings would suggest refraining from antibiotics and doing what we call watchful waiting," she told Reuters Health."
"We have to remain watchful on all fronts if this nation is to succeed."