Samadhik is not a standard, well-attested Jain technical term in the main scriptures. In Jainism you are more likely to meet_related terms like:

• Samādhi (absorption or deep meditative absorption): a state of concentrated mental focus, described in Jain yoga and meditation literature. It is a profound inner state, often discussed in the context of spiritual practices and yogic discipline.
• Samayik (also spelled samaiya/saamaiya in prakrit): a structured practice of equal-minded meditation for a fixed period, observed by both Śvētāmbara and Digambara traditions as one of the essential duties for laypersons and monks alike. Its aim is to stabilize the chetana (consciousness) in the present moment and reduce karmic inflow, leading toward equanimity and right conduct.

If you have a specific verse or source where you saw "samadhik," sharing that context could help pinpoint the exact Jain meaning and tradition (Digambara vs. Śvetāmbara).