Permanent, a.
Etymology: [L. permanens, -entis, p.pr. of permanere to stay or remain to the end, to last; per + manere to remain: cf. F. permanent. See Per-, and Mansion.]
Continuing in the same state, or without any change that destroys form or character; remaining unaltered or unremoved; abiding; durable; fixed; stable; lasting; as, a permanent impression. Eternity stands permanent and fixed. Dryden. Permanent gases (Chem. & Physics), hydrogen, oxygen, nitrogen, and carbon monoxide; -- also called incondensible or incoercible gases, before their liquefaction in 1877. -- Permanent way, the roadbed and superstructure of a finished railway; -- so called in distinction from the contractor's temporary way. -- Permanent white (Chem.), barium sulphate (heavy spar), used as a white pigment or paint, in distinction from white lead, which tarnishes and darkens from the formation of the sulphide.
Syn. -- Lasting; durable; constant. See Lasting.
Shades of meaning
Durable (L. durus, hard) is said almost wholly of material substances that resist wear; lasting is said of either material or immaterial things. Permanent is a word of wider meaning; a thing is permanent which is not liable to change; as, a permanent color; buildings upon a farm are called permanent improvements. Enduring is a higher word, applied to that which resists both time and change; as, enduring fame.