What is (a) A small cavity, tubular depression, or sac; as, a hair follicle. (b) A simple gland or glandular cavity; a crypt. (c) A small mass of adenoid tissue; as, a lymphatic follicle called?

follicle — (Anat.) (a) A small cavity, tubular depression, or sac; as, a hair follicle. (b) A simple gland or glandular cavity; a crypt. (c) A small mass of adenoid tissue; as, a lymphatic follicle. (Webster's 1913.)

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