a liquid used for writing that does not become visible until it has been treated with chemicals, heat, ultraviolet light, etc
noun 1. (in architectural shades and shadows) a three-dimensional space occupied by the shadow projected by a solid and within which a surface is in shadow.
[in-viz-uh-buh l] /ɪnˈvɪz ə bəl/ adjective 1. not visible; not perceptible by the eye: invisible fluid. 2. withdrawn from or out of sight; hidden: an invisible seam. 3. not perceptible or discernible by the mind: invisible differences. 4. not ordinarily found in financial statements or reflected in statistics or a listing: Goodwill is an invisible […]
[in-vi-tey-shuh n] /ˌɪn vɪˈteɪ ʃən/ noun 1. the act of . 2. the written or spoken form with which a person is . 3. something offered as a suggestion: an invitation to consider a business merger. 4. attraction or incentive; allurement. 5. a provocation: The speech was an invitation to rebellion. adjective 6. . /ˌɪnvɪˈteɪʃən/ […]
[in-vi-tey-shuh-nl] /ˌɪn vɪˈteɪ ʃə nl/ adjective 1. restricted to participants who have been : an invitational track meet. noun 2. an event, as a sports competition or an art exhibit, restricted to those who have been to participate.