Search Result for "pessimal": 
Wordnet 3.0

ADJECTIVE (1)

1. of an organism's environment; least favorable for survival;
[syn: pessimal, pessimum(a)]


The Collaborative International Dictionary of English v.0.48:

pessimal \pes"si*mal\ adj. Least favorable for survival; -- of an organism's environment. Syn: pessimum(prenominal). [WordNet 1.5]
WordNet (r) 3.0 (2006):

pessimal adj 1: of an organism's environment; least favorable for survival [syn: pessimal, pessimum(a)]
The Jargon File (version 4.4.7, 29 Dec 2003):

pessimal /pes'im?l/, adj. [Latin-based antonym for optimal] Maximally bad. ?This is a pessimal situation.? Also pessimize vt. To make as bad as possible. These words are the obvious Latin-based antonyms for optimal and optimize, but for some reason they do not appear in most English dictionaries, although ?pessimize? is listed in the OED.
The Free On-line Dictionary of Computing (30 December 2018):

pessimal /pes'im-l/ (Latin-based antonym for "optimal") Maximally bad. "This is a pessimal situation." Also "pessimise" To make as bad as possible. These words are the obvious Latin-based antonyms for "optimal" and "optimise", but for some reason they do not appear in most English dictionaries, although "pessimise" is listed in the OED. [Jargon File] (1995-02-01)