1. (a.) Net having the sense of hearing; deaf.

2. (a.) Unheard.

3. (a.) Involving surds; not capable of being expressed in rational numbers; radical; irrational; as, a surd expression or quantity; a surd number.

4. (a.) Uttered, as an element of speech, without tone, or proper vocal sound; voiceless; unintonated; nonvocal; atonic; whispered; aspirated; sharp; hard, as f, p, s, etc.; -- opposed to sonant. See Guide to Pronunciation, //169, 179, 180.

5. (n.) A quantity which can not be expressed by rational numbers; thus, 2 is a surd.

6. (n.) A surd element of speech. See Surd, a., 4.

Gaussian integer accented algebraic number algorismic algorithmic aliquot allophone alveolar apical apico-alveolar apico-dental articulated articulation aspiration assimilated assimilation back barytone bilabial broad cacuminal cardinal cardinal number central cerebral check checked close complex number consonant consonantal continuant deaf deaf and dumb deaf-eared deaf-mute deafened decimal defective number dental differential digital diphthong dissimilated dissimilation dorsal dull-eared earless epenthetic vowel even even number explosive exponential figural figurate figurative finite finite number flat fraction fractional front glide glossal glottal glottalization guttural hard hard of hearing heavy high imaginary imaginary number impair impossible infinite infinity integer integral intonated irrational irrational number labial labialization labiodental labiovelar laryngeal lateral lax light lingual liquid logarithmic logometric low manner of articulation mid mixed number modification monophthong monophthongal morphophoneme mute muted narrow nasal nasalized negative numeral numerary numerative numeric occlusive odd open ordinal oxytone pair palatal palatalized parasitic vowel peak pharyngeal pharyngealization pharyngealized phone phoneme phonemic phonetic phonic pitch pitched plosive polygonal number positive possible posttonic prime prime number prothetic vowel pure imaginary radical rational rational number real real number reciprocal rectangular number retroflex round number rounded segmental phoneme semivowel serial number soft sonant sonority speech sound stone-deaf stop stopped stressed strong stunned submultiple syllabic syllabic nucleus syllabic peak syllable tense thick thick of hearing throaty tonal tone-deaf tonic transcendental transcendental number transfinite number transition sound triphthong twangy unaccented unhearing unrounded unstressed velar vocable vocalic vocoid voice voiced voiced sound voiceless voiceless sound voicing vowel vowellike weak whole number wide word-deaf