Think of 'counteract' as pushing back against a force, idea, or trend to lessen its impact. Wearing a hat will counteract the sun's glare while driving.
Pro Tip 2/3
Not Instant
'Counteract' usually involves a process or effort over time, not an immediate cancellation of effects. Drinking water throughout the day can counteract dehydration.
Pro Tip 3/3
Not Always Complete
Using 'counteract' does not guarantee complete negation; it means to diminish the strength or effect. Taking vitamins may help counteract nutrient deficiencies.