Lust is not always negative, and is the translation from several words.

Negative:

Desire for what is forbidden. Every good thing that God has given can be perverted and made ugly.

Positive:

It could simply mean a longing or desire as when Jesus said this:

Luke 22:15 And he said to them, With desire I have desired to eat this passover with you before I suffer:

New Testament

1939 epithumia ep-ee-thoo-mee'-ah
from 1937; TDNT-3:168,339; {See TDNT 316} n f
AV-lust 31, concupiscence 3, desire 3, lust after 1; 38
1) desire, craving, longing, desire for what is forbidden, lust

3715 orexis or'-ex-is
from 3713; TDNT-5:447,727; {See TDNT 561} n f
AV-lust 1; 1
1) desire, longing, craving for
2) eager desire, lust, appetite
2a) used both in a good and a bad sense, as well of natural and lawful and even of proper cravings (of appetite for food), also of corrupt and unlawful desires

1937 epithumeo ep-ee-thoo-meh'-o
from 1909 and 2372; TDNT-3:168,339; {See TDNT 316} v
AV-desire 8, covet 3, lust 3, lust after 1, fain 1; 16
1) to turn upon a thing
2) to have a desire for, long for, to desire
3) to lust after, covet
3a) of those who seek things forbidden

3730 horme hor-may’
of uncertain affinity; TDNT-5:467,730; {See TDNT 565} n f
AV-assault 1, not tr 1; 2
1) a violent motion, impulse
2) a hostile movement, onset, assault

154 aiteo ahee-teh’-o
of uncertain derivation; TDNT-1:191,30; {See TDNT 38} v
AV-ask 48, desire 17, beg 2, require 2, crave 1, call for 1; 71
1) to ask, beg, call for, crave, desire, require

2309 thelo thel’-o or εθελω ethelo eth-el’-o in certain tenses θελεω theleo thel-eh’-o and εθελεω etheleo eth-el-eh’-o which are otherwise obsolete
apparently strengthened from the alternate form of 138; TDNT-3:44,318; {See TDNT 303} v
AV-will/would 159, will/would have 16, desire 13, desirous 3, list 3, to will 2, misc 4; 210
1) to will, have in mind, intend
1a) to be resolved or determined, to purpose
1b) to desire, to wish
1c) to love
1c1) to like to do a thing, be fond of doing
1d) to take delight in, have pleasure

2307 thelema thel’-ay-mah
from the prolonged form of 2309; TDNT-3:52,318; {See TDNT 303} n n
AV-will 62, desire 1, pleasure 1; 64
1) what one wishes or has determined shall be done
1a) of the purpose of God to bless mankind through Christ
1b) of what God wishes to be done by us
1b1) commands, precepts
2) will, choice, inclination, desire, pleasure

2107 eudokia yoo-dok-ee’-ah
from a presumed compound of 2095 and the base of 1380; TDNT-2:742,273; {See TDNT 269} n f
AV-good pleasure 4, good will 2, seem good + 1096 2, desire 1; 9
1) will, choice
1a) good will, kindly intent, benevolence
2) delight, pleasure, satisfaction
3) desire
3a) for delight in any absent thing easily produces longing for it

3806 pathos path'-os NOTE: only used as lust one time, and the definition is not what we would normally associate with lust.
from the alternate of 3958; TDNT-5:926,798; {See TDNT 606} n n
AV-inordinate affection 1, affection 1, lust 1; 3
1) whatever befalls one, whether it be sad or joyous
1a) spec. a calamity, mishap, evil, affliction
2) a feeling which the mind suffers
2a) an affliction of the mind, emotion, passion
2b) passionate deed
2c) used by the Greeks in either a good or bad sense
2d) in the NT in a bad sense, depraved passion, vile passions

Old Testament

02530 chamad khaw-mad’
a primitive root;;{ See TWOT on 673}
AV-desire 11, covet 4, delight 2, pleasant 1, beauty 1, lust 1, delectable things 1; 21
v
1) to desire, covet, take pleasure in, delight in
1a) (Qal) to desire
1b) (Niphal) to be desirable
1c) (Piel) to delight greatly, desire greatly
n f
2) desirableness, preciousness

08378 ta’avah tah-av-aw’
from 0183 (abbrev); n f; {See TWOT on 40 @@ "40d"}
AV-desire 13, lust 1, greedily 1, pleasent 1, misc. 4; 20
1) desire
1a) desire, wish, longings of one’s heart
1a1) lust, appetite, covetousness (bad sense)
1b) thing desired, object of desire

05315 nephesh neh’- fesh
NOTE: When nephesh is used as lust, it is referring to the desires of the mind.
from 05314; n f; {See TWOT on 1395 @@ "1395a"}
AV-soul 475, life 117, person 29, mind 15, heart 15, creature 9, body 8, himself 8, yourselves 6, dead 5, will 4, desire 4, man 3, themselves 3, any 3, appetite 2, misc 47; 753
1) soul, self, life, creature, person, appetite, mind, living being, desire, emotion, passion
1a) that which breathes, the breathing substance or being, soul, the inner being of man
1b) living being
1c) living being (with life in the blood)
1d) the man himself, self, person or individual
1e) seat of the appetites
1f) seat of emotions and passions
1g) activity of mind
1g1) dubious
1h) activity of the will
1h1) dubious
1i) activity of the character
1i1) dubious