- Three-thousandth Num
- Three-tier Adj Noun
- Three-tiered Adj
- Three-toed Adj
- Three-toothed Adj
- Three-valent Adj
- Three-voice Adj
- Three-way Adj Noun Adv
- Three-wheel Adj
- Three-wheeled Adj
- Three-wheeler Noun Adj
- Three-winged Adj
- Three-year Adj
- Three-year-old Adj Noun
- Threefold Adj Adv
- Threeness Noun
- Threepence Noun
- Threepenny Adj
- Threeping Noun Pres. Participle
- Threescore Adj Noun Num
- Threesided Adj
- Threesome Noun Adj
- Threevaluedness Noun
- Thremmatology Noun
- Threnetic Adj
- Threnody Noun Pnoun
- Threonine Noun Adj
- Threonyl Noun Adj
- Threose Noun Adj
- Threpsology Noun
- Thresh Verb Noun
- Thresher Noun Adj
- Thresherman Noun Adj
- Threshing Noun Pres. Participle
- Threshold Noun Adj
- Threshold-defining Pres. Participle
- Threshold-like Adj
- Threshold-setting Noun Pres. Participle
- Thresholding Noun Pres. Participle
- Thresholdless Adj
- Thrice Adv Adj
- Thrift Noun Adj
- Thrifted Adj Past Participle
- Thrifter Noun
- Thriftier
- Thriftily Adv
- Thriftiness Noun
- Thriftless Adj
- Thriftlessness Noun
- Thrifty Adj
- Thrill Noun Verb Adj
- Thrill-seeker Noun Adj
- Thrilled Past Participle
- Thriller Noun Adj Pnoun
- Thrilling Adj Noun
- Thrillingly Adv
- Thrips Noun Adj
- Thrive Verb
- Thrive along Verb
- Thrive around Verb