verb, -took, -tak⋅en, -tak⋅ing.| 1. | to take upon oneself, as a task, performance, etc.; attempt: She undertook the job of answering all the mail. |
| 2. | to promise, agree, or obligate oneself (fol. by an infinitive): The married couple undertook to love, honor, and cherish each other. |
| 3. | to warrant or guarantee (fol. by a clause): The sponsors undertake that their candidate meets all the requirements. |
| 4. | to take in charge; assume the duty of attending to: The lawyer undertook a new case. |
| 5. | Archaic. to engage oneself by promise; give a guarantee, or become surety. |