> as lemmas
undevelopable
undevelopable adj. 
/ˌəndiˈvɛləpəb(ə)l/
Brit. /ˌʌndᵻˈvɛləpəbl/
, /ˌʌndᵻˈvɛləpəbl/U.S. /ˌəndəˈvɛləpəb(ə)l/
, /ˌəndəˈvɛləpəb(ə)l//ˌəndiˈvɛləpəb(ə)l/ΚΠ
1828 Trans. Royal Irish Acad. 15 72 The tangent plane to an undevelopable pencil does not touch the pencil in the whole extent of a ray.
1962 Financial Times 6 Dec. 7/6 Somalia..seems not only underdeveloped but undevelopable.
2001 Nat. New Eng. May 29/3 The brokered deal had the land trust..selling an undevelopable lot nearby.
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as lemmas