Narrow
Part of speech: verb
Definition: To reduce in width or extent; to contract. To get narrower.
Part of speech: adjective
Definition: having a small width; not wide; slim; slender; having opposite edges or sides that are close, especially by comparison to length or depth. Restrictive; without flexibility or latitude.
Example sentence: I think that intelligence is such a narrow branch of the tree of life - this branch of primates we call humans. No other animal, by our definition, can be considered intelligent. So intelligence can't be all that important for survival, because there are so many animals that don't have what we call intelligence, and they're surviving just fine.
Specialize
Part of speech: verb
Definition: To mention specially; to particularize.To apply to some specialty or limited object; to assign to a specific use; as, specialized knowledge.To supply with an organ or organs having a special function or functions.
Example sentence: To generalize on women is dangerous. To specialize on them is infinitely worse.