American silversmith remembered for his midnight ride (celebrated in a poem by Longfellow) to warn the colonists in Lexington and Concord that British troops were coming (1735-1818)
lengthen in time; cause to be or last longer; "We prolonged our stay"; "She extended her visit by another day"; "The meeting was drawn out until midnight"
lengthen or extend in duration or space; "We sustained the diplomatic negotiations as long as possible"; "prolong the treatment of the patient"; "keep up the good work"
keep in one's mind; "I cannot retain so much information"
secure and keep for possible future use or application; "The landlord retained the security deposit"; "I reserve the right to disagree"
allow to remain in a place or position; "We cannot continue several servants any longer"; "She retains a lawyer"; "The family's fortune waned and they could not keep their household staff"; "Our grant has run out and we cannot keep you on"; "We kept the work going as long as we could"
hold within; "This soil retains water"; "I retain this drug for a long time"