cog·ni·tive 
(kŏgnĭ-tĭv)
(kŏgnĭ-tĭv)adj.
Of, characterized by, involving, or relating to cognition: "For the person experiencing cognitive decline, the slow loss of coherent speech will be compounded by a declining ability to draw conclusions" (Joanne Koenig Coste).
cogni·tive·ly adv.
- off-the-shelf
- off the shelf
- off the top of head
- off the top of (one's) head
- off the top of one's head
- off the wagon
- off-the-wall
- off the wall
- off the wind
- off-track
- off-track betting
- off-white
- off year
- O'Flaherty
- of late
- ofloxacin
- OFM
- of necessity
- of (one's) word
- of one's word
- of sorts/a sort
- of sorts sort
- oft
- often
- oftentimes