Only in Igbo 39
What this means for learners
Igbo and Yao share 26 sounds — roughly 40% of Yao's inventory overlaps with Igbo. Shared sounds are ones a speaker already knows from their native language and will generally produce and perceive accurately without explicit training.
The 23 sounds found only in Yao represent the greatest pronunciation challenge for Igbo speakers. The adult brain tends to map unfamiliar sounds onto the closest native equivalent — a process that produces the characteristic "accent" of a second-language speaker. Learning to hear and produce these sounds as distinct requires focused ear training, not just repetition.
Conversely, Igbo has 39 sounds not used in Yao. Native Yao speakers learning Igbo will face the mirror-image challenge with these sounds.
Phoneme inventories from PHOIBLE. Data reflects one documented inventory per language; some variation exists across dialects and sources.