Oracle Text

Counter target activated ability from an artifact, creature, enchantment, or land. That permanent's activated abilities can't be activated this turn. (Mana abilities can't be targeted.)

Draw a card.

Card Rulings

10/4/2004 This card targets the ability, and not the permanent itself.
6/8/2016 Activated abilities contain a colon. They’re generally written “[Cost]: [Effect].” Some keywords are activated abilities and will have colons in their reminder text.