voiceless th

Core Rule

Voiceless TH refers to the /θ/ sound produced by the spelling th, with airflow friction and no vocal cord vibration. It commonly appears in lexical words and academic roots.

Articulation Guide

Place the tongue tip lightly against the upper teeth or slightly between them; keep lips relaxed; push steady air without voicing.

Word Analysis

• sympathetic /ˌsɪm.pəˈθeθ.ɪk/: both th sounds are /θ/; maintain continuous airflow.
• theatrical /θiˈæ.trɪ.kəl/: initial th stays voiceless.
• theoretical /ˌθiː.əˈrɛt.ɪ.kəl/: despite vowel complexity, th remains /θ/.

Pitfalls

Do not confuse /θ/ with voiced /ð/ (as in this), or substitute s, t, f.