Mesti

Mesti is a modal verb used in Malay and Indonesian to express necessity, obligation, or strong probability. In everyday speech, it commonly conveys a sense of "must" or "have to," and both languages employ it without inflection.

In deontic use, mesti signals the speaker’s assessment of what is required rather than an externally imposed rule. For example, Saya mesti pergi sekarang means "I must go now" or "I have to go now," a soft but clear obligation. In Malay, it can also appear with internal determination, as in Saya mesti belajar, indicating a personal commitment to study.

In epistemic use, mesti indicates likelihood or assumption, similar to "probably" or "must be." For instance, Dia mesti sudah makan means "He must have already eaten," and Mesti hujan hari ini means "It must be raining today" or "It will probably rain today." This sense is common in casual conversation and reflects inference rather than obligation.

Mesti coexists with other modals such as harus, wajib, and perlu. Harus or wajib are generally stronger and more normative, while perlu is more neutral and task-focused. Mesti tends to be more flexible and context-dependent, with nuance shaped by tone, situation, and regional variation.

Etymology of mesti is not definitively established; it is a native Malayic term that has long been part of the lexicon in Malay and Indonesian, with cognates appearing across the broader Malayic language family. It is widely used across Malaysia, Indonesia, Singapore, and Brunei, and remains common in informal speech, media, and education.

See also: Malay language, Indonesian language, modal verbs, epistemic modality.