145 aisthētḗrion (a neuter noun derived from aio, "perceive, discern through the senses") – properly, "the organ of sense" (BAGD), emphasizing the result of sensory experience (sensation) – i.e. moral feeling to know what is right or wrong in God's eyes (used only in Heb 5:14 and in the plural).

"145 (aisthētērion, neuter noun) focuses on the principle of sense and especially its result. 144 /aísthēsis (the feminine cognate) is the brand of sense-discernment which shrewdly sizes things up. 145 (aisthētḗrion) is "the concrete organ of sense, becoming virtually a habitual ability which must be developed and enables believers to distinguish between the spirits. It is a spiritual gift which must be developed in practice" (DNTT, 2, 391).

[Like 144 /aísthēsis, 145 /aisthētḗrion comes from 143 /aisthánomai ("to perceive with the aid of the physical senses").]

a sense

From a derivative of aisthanomai; properly, an organ of perception, i.e. (figuratively) judgment -- senses.

see GREEK aisthanomai

ἀρθήτω — 1 Occ.
ἀρθῶσιν — 1 Occ.
ἦραν — 12 Occ.
ἤρατε — 3 Occ.
ἦρεν — 6 Occ.
ἦρκεν — 1 Occ.
ἠρμένον — 1 Occ.
ἤρθη — 3 Occ.
αἴσθωνται — 1 Occ.
αἰσθήσει — 1 Occ.
αἰσχροκερδῆ — 1 Occ.
αἰσχροκερδεῖς — 1 Occ.
αἰσχροκερδῶς — 1 Occ.
αἰσχρολογίαν — 1 Occ.
αἰσχρὸν — 3 Occ.
αἰσχροῦ — 1 Occ.
αἰσχρότης — 1 Occ.
αἰσχύνας — 1 Occ.
αἰσχύνῃ — 2 Occ.
αἰσχύνης — 3 Occ.