felt (n.)youdaoicibaDictYouDict
unwoven fabric matted together by rolling or beating while wet, Old English felt "felt," from West Germanic *feltaz "something beaten, compressed wool" (cognates: Old Saxon filt, Middle Dutch vilt, Old High German filz, German Filz, Danish filt), from Proto-Germanic *felt- "to beat," from PIE *pel- (6) "to thrust, strike, drive" (source also of Old Church Slavonic plŭstĭ), with a sense of "beating" (see pulse (n.1)). Compare filter (n.). Felt-tipped pen (or -tip) is from 1953.
marker (n.)youdaoicibaDictYouDict
Old English mearcere "writer, notary" (glossing Latin notarius "clerk"), literally "one who marks," agent noun from mark (v). Not found again until late 15c., hence modern use is perhaps a separate formation. Meaning "monument stone" is from 1888. Meaning "felt-tipped marker pen" is from 1951, so called because their purpose was to "highlight" text.