∙ simple past tense and past participle of concentrate
concentrate
Verb
∙ To bring to, or direct toward, a common center; to unite more closely; to gather into one body, mass, or force. transitive, intransitive
∙ To increase the strength and diminish the bulk of, as of a liquid or an ore; to intensify, by getting rid of useless material; to condense . as opposed to 'dilute'
∙ To approach or meet in a common center; to consolidate.
∙ To focus one's thought or attention (on). intransitive