ectomorphec‧to‧morph /ˈektəʊˌmɔːf $ ˈektoʊˌmɔːrf/ noun [countable] technical 
someone with a naturally thin body
someone with a naturally thin body- extortionately
- extortionist
- extra
- extra-
- extract
- extraction
- extractor
- extracurricular
- extraditable
- extradite
- extradition
- extrajudicial
- extramarital
- extramural
- extraneous
- extranet
- extraordinaire
- extraordinarily
- extraordinary
- extraordinary rendition
- extrapolate
- extrapolation
- extra-sensory perception
- extraterrestrial
- extraterritorial