M'ASSY, adjective Heavy; weighty; ponderous; bulky and heavy; as a massy shield; a massy rock. The yawning rocks in massy fragments fly. M'ASSIVE, adjective In mineralogy, in mass; having a crystalline structure, but not a regular form. We say, a mineral occurs massive.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI