Nikkhepakaṇḍa

Abhidhammapiṭaka · Dhammasaṅgaṇī · Vol. 34 · Section 818

[818] Therein, what is doubt (vicikicchā)? One is uncertain about the Teacher, doubts, … rigidity of mind (citta), mental perplexity — this is called doubt.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 3 other places