the ear: the body part used for hearing, and by extension the act of paying attention to what is heard.
TranslatabilityPartialCertaintySettled
This is the ordinary word for the ear, the organ on the side of the head. The Bible uses it both for the physical ear you can touch and for what the ear is for: taking in and heeding what is said. Because hearing in this world is tied to obeying, the ear becomes a picture of attention itself. To have an open ear is to be ready to listen; a closed or heavy ear is a picture of a person who will not.
Much of the word's force comes from a few set phrases. To bring words "to the ears of" someone means to say them out loud so that person hears, and "in the ears of" a crowd means in their hearing, where everyone present can take it in. To "incline the ear" is to bend toward a speaker and pay close attention, and it is asked both of people and of God. To "open" or "uncover" someone's ear is to let them in on something they could not otherwise know, so the phrase comes to mean revealing a secret or a message.
The same word covers God's ear as well as the human one. When the Bible asks God to incline his ear or to let his ears be attentive, it is praying that God will listen and act, not describing a body part. Whether the ear is human or divine, the point is the same: hearing that leads to a response.
Nuances
1athe physical ear, the organ on the side of the head.
Names the ear as the organ that hears, so it stands for a message actually reaching people: a text is read out and a report is told "in the ears of" those present.Gen 20:8Exo 24:7Deu 31:11
Is used of God himself listening, whether a cry reaching his hearing or a plea that he bend down and pay attention.2Sa 22:72Ki 19:16
Carries a settled turn of phrase for letting someone in on a secret, literally uncovering a person's ear so that what was hidden is now told.1Sa 9:151Sa 20:2
Is the ear that gets pierced at the doorpost when a servant chooses to stay for life, making the whole organ a lasting sign of belonging.Exo 21:6Deu 15:17
Is simply the visible ear people hang jewelry on, with gold rings taken out of the ears of a household.Gen 35:4Exo 32:2
Both
Both name the same physical body part, and in these ceremonies they stand side by side in one phrase, the tip of the ear, with the wider word supplying the ear and the narrower one the tip.Exo 29:20Lev 8:23
Both belong to the ceremonies that set a person apart, where marking the ear signals that this person now belongs to God and is meant to listen to him.Lev 14:14Lev 8:24
Picks out one small piece of the ear, the soft tip at its lower edge, rather than the ear as a whole.Exo 29:20Lev 8:23
Turns up only in ceremonies, as the spot where blood and then oil are dabbed on a priest being installed or on a person declared clean after a skin disease.Lev 8:24Lev 14:14Lev 14:17
Is always the tip of the right ear, and always the first of three matched points, ear tip then right thumb then right big toe, so the touch runs over the whole person.Lev 14:25Lev 14:28
ozen in the other biblical languages
οὖςGreek“ear”the Greek word for the ear, used the same way for both the body part and a readiness to hear ("let the one who has ears hear").
The ear is the physical point of ritual consecration and cleansing: blood and oil were placed on the tip of the right ear of priests at their ordination and of a healed person at his purification.Exo 29:20Lev 14:14
The pierced ear marks a lifelong servant: one who chose to stay with his master was brought to the door and had his ear bored through with an awl.Exo 21:6Deu 15:17
It anchors the idiom to uncover someone's ear, meaning to disclose a secret or let a person in on a plan.1Sa 9:15Rut 4:4
Both
Both name the literal organ of hearing on the head.Exo 29:20Luk 22:50
Both stand for spiritual receptivity, so ears that do not hear is the stock picture of a people closed to God, an image the New Testament draws straight from the Old.Deu 29:4Rom 11:8
Both can mean the reach of someone's hearing: to speak or read something in the ears of people is to say it where they can take it in.Gen 20:8Luk 4:21
It carries the fixed refrain whoever has ears to hear, let him hear, a set closing formula that Jesus attaches to his parables and the risen Christ repeats to each of the seven churches.Mrk 4:9Rev 2:7
names the physical ear as a body part that can be handled, touched with blood in a ceremony or pierced with an awlExo 29:20Lev 8:23Exo 21:6Deu 15:17
carries the fixed phrase in the ears of, meaning within a person's hearing, used when a text is read aloud to a gathered peopleExo 24:7Deu 31:11Gen 20:8Gen 23:16
carries the idiom uncover the ear, meaning to disclose a secret or let someone in on a plan1Sa 9:151Sa 20:21Sa 22:81Sa 22:17
Both
both can name the bodily ear, the organ through which sound and speech are received1Co 12:17Mrk 7:351Sa 3:11Gen 35:4
names the news or report about someone that travels from person to person, a meaning the Hebrew ear-word never carriesMat 4:24Mat 14:1Mrk 1:28Mat 24:6
names the act of hearing itself, and by extension the message that is heard, so that it becomes the thing faith rests onRom 10:17Rom 10:16Jhn 12:38Gal 3:2
What scholars say about ozen
The standard lexicons treat this as a single word, the ear, whose uses fan out from the physical organ to the act of attention and to a set of fixed phrases. BDB and HALOT group the literal ear, the ear as the seat of hearing and obedience, and the idioms for speaking in someone's hearing and for revealing a matter. TDOT and TWOT stress that in Hebrew thought hearing and obeying are closely tied, so the ear stands for willing attention, and that asking God to incline or open his ear is a way of praying for his response, part of the wider biblical use of body parts to speak of God.
Sources
BDB (Brown-Driver-Briggs), s.v. אֹזֶןlexicon
HALOT (Koehler-Baumgartner), s.v. אֹזֶןlexicon
David J. A. Clines, ed., The Dictionary of Classical Hebrew (DCH), s.v. אֹזֶןlexicon
H.-J. Fabry, "אֹזֶן," in Theological Dictionary of the Old Testament (TDOT) 1:323-325dictionary
Leonard J. Coppes, "אֹזֶן," in Theological Wordbook of the Old Testament (TWOT), no. 57dictionary