Merriam-Webster Collegiate Dictionary - consent

 I. intransitive verb  Etymology: Middle English, from Anglo-French ~ir, from Latin ~ire, from com- + sentire to feel — more at sense  Date: 13th century  1. to give assent or approval ; agree ~ to being tested  2. archaic to be in concord in opinion or sentiment  Synonyms: see assent  • ~er noun  • ~ingly adverb  II. noun  Date: 14th century  1. compliance in or approval of what is done or proposed by another ; acquiescence he shall have power, by and with the advice and ~ of the Senate, to make treaties — U.S. Constitution  2. agreement as to action or opinion; specifically voluntary agreement by a people to organize a civil society and give authority to the government