to focus or direct (one's mind or attention) on or towards a common centre or objective
Depend upon it, Sir, when a man knows he is to be hanged in a fortnight, it concentrates his mind wonderfully — Dr Johnson
to gather (something) into one body, mass, or force
Power was concentrated in a few able hands
to make (a solution) less dilute
to express or exhibit (something) in condensed form
The author concentrates his message in the last paragraph
(often + on) to direct one's efforts or attention on a task, etc
to gather or collect
to go towards or meet at a common centre
concentrative /-traytiv/ adj
concentrator noun
[French concentrer from con- + Latin centrum: see centre1]