/ˈlimənl/
Adjective
1. Pertaining to a threshold or entrance. (wiktionary.org)
2. Relating to a beginning or first stage of a process; inceptive; inchoative; marginal; insignificant. (wiktionary.org)
3. Pertaining to a stimulus just strong enough to excite a tissue, e.g., nerve or muscle. (biology-online.org)
4. Occupying a position at, or on both sides of, a boundary or threshold. (Google Dictionary)
Word origin: From Latin limen “threshold, cross-piece, sill.”