| a chattering or flighty, light-headed person. |
| a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question. |
antigen an·ti·gen (ān'tĭ-jən)
n.
Any of various substances, including toxins, bacteria, and the cells of transplanted organs, that when introduced into the body stimulate the production of antibodies. Also called allergen, immunogen.
| antigen (ān'tĭ-jən) Pronunciation Key
A substance that stimulates the production of an antibody when introduced into the body. Antigens include toxins, bacteria, viruses, and other foreign substances. Compare antibody. See Note at blood type. |