- Thorium-232
- Thorotrast
- Thought disorder
- Thought insertion
- Thought stopping
- Thought suppression
- Thought withdrawal
- Thought-action fusion
- Thousand-yard stare
- Threadworms
- Threat assessment
- Threats
- Three Rs
- Three-photon microscopy
- Three-term contingency
- Threitol
- Threohydrobupropion
- Threonic acid
- Threonine
- Threshold dose
- Threshold limit value
- Threshold model
- Threshold potential
- Thrifty gene hypothesis
- Thrifty phenotype
- Thriving
- Throat
- Throat cancer
- Throat irritation
- Throat lozenges
- Thrombectomy
- Thrombin
- Thrombin receptor
- Thrombin time
- Thrombin-antithrombin complex
- Thromboangiitis obliterans
- Thrombocyte
- Thrombocytopenia
- Thrombocytopenic purpura
- Thrombocytosis
- Thromboelastography
- Thromboelastometry
- Thromboembolism
- Thrombolysis
- Thrombolytic drug
- Thrombomodulin
- Thrombophilia
- Thrombophlebitis
- Thromboplastin
- Thrombopoiesis
- Thrombopoietin
- Thrombopoietin receptor
- Thromboprophylaxis
- Thrombosis
- Thrombospondin
- Thrombotic microangiopathies
- Thrombotic microangiopathy
- Thromboxane
- Thromboxane A2
- Thromboxane receptor
- Thrombus
- Throwing
- Thrush
- Thuja
- Thuja occidentalis
- Thujone
- Thujopsene
- Thumb
- Thumb hypoplasia
- Thumb sucking
- Thunderclap headache
- Thunderstorm asthma
- Thylakoid membrane
- Thylakoid membranes
- Thylakoids
- Thyme
- Thyme oil
- Thymectomy
- Thymic carcinoma
- Thymic epithelial cells
- Thymic involution
- Thymic stromal lymphopoietin
- Thymidine
- Thymidine kinase
- Thymidine monophosphate
- Thymidine phosphorylase
- Thymidylate kinase
- Thymidylate synthase
- Thymidylate synthase inhibitor
- Thymine
- Thymine dimers
- Thymine glycol
- Thymine-DNA glycosylase
- Thymineless death
- Thymocytes
- Thymoglobulin
- Thymol
- Thymolphthalein
- Thymoma
- Thymopoietin
- Thymoquinone
- Thymosin beta 4
- Thymus
- Thymus gland
- Thymus serpyllum
- Thymus vulgaris
- Thyroarytenoid muscle
- Thyrocervical trunk
- Thyroepiglottic ligament
- Thyroglobulin
- Thyroglossal cyst
- Thyroglossal duct
- Thyroglossal duct cyst
- Thyrohyoid membrane
- Thyroid
- Thyroid acropachy
- Thyroid adenoma
- Thyroid antibody
- Thyroid cancer
- Thyroid carcinoma
- Thyroid cartilage
- Thyroid crisis
- Thyroid cyst
- Thyroid disease
- Thyroid disease in pregnancy
- Thyroid diseases
- Thyroid dysgenesis
- Thyroid dyshormonogenesis
- Thyroid follicle
- Thyroid follicular cell
- Thyroid function
- Thyroid function test
- Thyroid function tests
- Thyroid gland
- Thyroid hormone
- Thyroid hormone receptor
- Thyroid hormone receptor alpha
- Thyroid hormone resistance
- Thyroid hormones
- Thyroid isthmus
- Thyroid lymphoma
- Thyroid neoplasm
- Thyroid nodules
- Thyroid peroxidase
- Thyroid stimulating hormone
- Thyroid stimulating immunoglobulin
- Thyroid storm
- Thyroid-stimulating hormone
- Thyroidectomy
- Thyroiditis