IMMOBILE
fast, firm, immobile
(adjective) securely fixed in place; “the post was still firm after being hit by the car”
immobile
(adjective) not capable of movement or of being moved
Source: WordNet® 3.1
Etymology
Adjective
immobile (not comparable)
not mobile, not movable
fixed, unable to be moved
Synonyms
• fixed
• sessile (botany)
• unmovable
Antonyms
• mobile
Source: Wiktionary
Im*mo"bile, a. Etym: [L. immobilis: cf. F. immobile. See Immobility.]
Definition: Incapable of being moved; immovable; fixed; stable. Prof.
Shedd.
Source: Webster’s Unabridged Dictionary 1913 Edition