- Theatrics
- Their name is legion
- Theme
- There is the rub
- There or thereabouts
- Thereabout
- Thermal capacity
- Thermal's
- Thermally
- Thermic effect
- Thermic stimulus
- Thermit
- Thermite
- Thermo
- Thermo metrical
- Thermodynamics
- Thermoelectric
- Thermoelectricity
- Thin
- Thin on top
- Thunderbird
- Think
- Think about
- Think better of
- Think of
- Think through
- Thinkable
- Thinkcentre
- Thoughtless
- Thrall
- Thrasher
- Thrawt
- Thread-paper
- Three days
- Three hundred
- Three qualities
- Through
- Through carriage
- Throw about
- Throw lupe
- Throw over
- Throw stones
- Throwing away
- Throwing down
- Tightwad
- Thrush
- Thrust aside
- Thrust oneself
- Thumb a lift
- Thumbs down
- Thump
- Thump impression
- Thunder-stroke
- Thundercloud
- Thwack
- Thy
- Thyme
- Thyself
- Tied to one's wife's apron strings
- Ties
- Tiger beetle
- Tiger mom
- Tight schedule
- Tightness
- Tightrope walk
- Tights
- Tiht garment
- Tilde
- Tiling
- Tinder-box
- Tindery
- Tinea
- Tingle
- Tingling
- Tiniest
- Tinkling anklet
- Tinning
- Tinospora
- Tinsmith
- Tintinnabulation
- Tip-off
- Tip-silly
- Tippet
- Tippler
- Tizzy
- To a frazzle
- To abandon
- To accept
- To achieve
- To add butter milk to milk
- To aim at
- To and fro
- To arrange
- To bale out
- To be abashed
- To be detained
- To be fed up
- To be filled up
- To be giddy
- To be hampered