The term ADD STAFF can be broken down into four crossword solutions: GROW, HIRE, HIRING, and LACE. GROW is an action verb that means to increase in size or number. HIRE is a verb that means to engage the services of someone for a fee. HIRING is the present participle of the verb HIRE, meaning to engage the services of someone for a fee. Lastly, LACE is a verb that means to add something to something else. All of these terms are related to the idea of adding staff, which is the process of bringing on new employees to a business or organization.